Re: [Repeater-Builder] Micor UHF Sensivity
Sinad is done with a 1000 Hz tone at 3KHz deviation and requires a meter that can notch out the 1K tone and measure the remaining noise. 20dBQ is done with no modulation 2 Vac of sq noise w/ no carrier then generate unmodulated carrier till the ACVM indicates 0.2 Vac A major difference in the two usually meant an alignment issue or some sort of problem in the back end of the receiver. Is the meter 4 circuit showing that the channel element is on frequency, and have you checked the alignment of the IF? Proponets of the Sinad method claimed that their way of doing the alignment would actually improve the overall sensitivity since the radio was being tested while receiving audio. Milt N3LTQ - Original Message - From: Tim Sawyer To: Repeater-Builder@yahoogroups.com Sent: Monday, September 06, 2010 3:48 PM Subject: Re: [Repeater-Builder] Micor UHF Sensivity I'm getting about 0.35 for 12 db SINAD. But that looks about 10 db quieting to me. What I typically do is open the squelch with no signal and set the volume to 2 Vac then crank up the signal to 0.2 vac. Isn't that 20 db, or am I missing something? -- Tim :wq On Sep 6, 2010, at 10:46 AM, Eric Lemmon wrote: spec is 0.5 uV without a preamp and 0.25 uV with a preamp, when using the 20 dB quieting method, and 0.35 and 0.175 respectively when using the 1 2 dB SINAD method
Re: [Repeater-Builder] Antenna ID
It's a Maxrad. The Ringo had the phasing element at the bottom in the form of a ring, hence the name. The Maxrad used the same theory but built in a different manner. Milt N3LTQ - Original Message - From: La Rue Communications To: Repeater-Builder@yahoogroups.com Sent: Friday, September 03, 2010 4:30 PM Subject: Re: [Repeater-Builder] Antenna ID THats two for MaxRad so far! So it will either be a MaxRad or a Ringo. Its incredibly light, and it looks very much like a light saber, which is what I am almost inclined to use it for, if it wasnt worth a few bucks! :) Its nice to know this may be frequency adjustable. I just wanted to be sure, now I am more sure than I started with. Thanks for the responses so far! John Hymes La Rue Communications 10 S. Aurora Street Stockton, CA 95202 http://tinyurl.com/2dtngmn - Original Message - From: Chuck Kelsey To: Repeater-Builder@yahoogroups.com Sent: Friday, September 03, 2010 1:25 PM Subject: Re: [Repeater-Builder] Antenna ID These style antennas are typically poor performers FYI. I wouldn't use it for anything important. Cushcraft started the design with their Ringo series, then several others copied the design. They were inexpensive, which was the only good feature. Chuck WB2EDV - Original Message - From: La Rue Communications To: Repeater-Builder@yahoogroups.com Sent: Friday, September 03, 2010 4:01 PM Subject: [Repeater-Builder] Antenna ID I figured this group would be in the know on how to ID an antenna without a sticker or any identification numbers engraved on it. I have an antenna that I found. It has no stickers of any kind, except for the This will kill you if you touch a wire sticker on it. Pictures attached are all I have. Its an N type connector and is roughly 4 feet in length. Is there any way to ID this with your traditional shop equipment? Thanks in advance! By the way, Kevin Custer, please email me! Thanks! John Hymes La Rue Communications 10 S. Aurora Street Stockton, CA 95202 http://tinyurl.com/2dtngmn -- No virus found in this incoming message. Checked by AVG - www.avg.com Version: 9.0.851 / Virus Database: 271.1.1/3111 - Release Date: 09/03/10 02:34:00
Re: [Repeater-Builder] Thru-Line Power Sensor?
These were used with Micor stations that had the optional wattmeter kit installed. The cable connected to the remainder of the kit whch consisted of a meter, foward/reflected power switch and calibration pot(s). The element is the same one that is used with the Motorola wattmeter and the remote metering kit on the R2001 service monitor. Milt N3LTQ - Original Message - From: La Rue Communications To: Repeater-Builder@yahoogroups.com Sent: Thursday, August 05, 2010 7:39 PM Subject: [Repeater-Builder] Thru-Line Power Sensor? Trying to confirm this is what I am looking at here. Motorola P/N reads TRN5323A. Google search yields an archived thread re-posted here on R/B from another site, but its kinda sparse with details and I want to be absolutely sure that this is what it is. Band spread of this unit is 50W 500-1000 MHz. Pic attached. Thanks in advance! John Hymes La Rue Communications 10 S. Aurora Street Stockton, CA 95202 http://tinyurl.com/2dtngmn
Re: [Repeater-Builder] Measuring duplexer insertion loss
In addition to what Jeff said in his posts, I usually run a test sweep on my HP8924 connecting the two cables together with a double female of the appropriate type. The result should be a flat line sweep but will usually show some amount of loss relative to the generator level/reference level. I note the amount of loss and either increase the generator output to place the line as near as possible to 0db or just remember to subtract it from the end reading. After I do the test sweep I connect the cabling to the device to be swept and proceed with measurements and tuning. - Original Message - From: cruizzer77 atlant...@gmx.ch To: Repeater-Builder@yahoogroups.com Sent: Friday, August 06, 2010 3:35 PM Subject: [Repeater-Builder] Measuring duplexer insertion loss Can somebody please explain how the insertion loss of a duplexer is properly measured using a HP 8920A (with specan). I'm pretty new to this instrument as well as duplexer work but am eager to learn. Thanks. 73 Martin P.S.: Is it correct that a duplexer that has 40 dB isolation in each leg does have 80 dB overall isolation? Yahoo! Groups Links
Re: [Repeater-Builder] Polyphaser EOL ?
Check that Polyphasor with an ohmeter, I'll bet you find a short or resistance from center to shield. Had one go out once, poor RX on a base station was the complaint. Found high VSWR. Polyphasor showed dead short from center to shield. Cracked the housing apart (with a cold chisel) and marveled at the construction. (:-'( It's nothing more than a gas tube across the coax line. Milt N3LTQ - Original Message - From: David Jordan To: Repeater-Builder@yahoogroups.com Sent: Thursday, August 05, 2010 1:14 PM Subject: [Repeater-Builder] Polyphaser EOL ? Hi folks, We noticed reduced sensitivity at one of our remote receivers recently. Went out to check things. All looked good. SWR to the receive antenna was good. Check it with and w/o Polyphaser in line. Replaced Polyphaser and tested again. same SWR but sensitivity much improved. Is this typical for a Polyphaser that has reached EOL? 73, Dave Wa3gin
Re: [Repeater-Builder] Desoldering MSR2000 RX PCB
Wattage is of less importance than tip temperature and size. Weller's better irons came with tips that were available in 3 ranges, approx 600, 70, and 800 degrees F. The 800 degree tips were the only ones that I have ever had any degree of success with. Other manufacturers use various types of schemes to adjust the tip temperature. A small narrow tip is fine for small work but will not do well for larger areas where a broad tip with more thermal mass will be more effective.. With most irons it becomes necessary to match the tip size and geometry with the job to be done. Milt - Original Message - From: Eric Grabowski ejgrabow...@yahoo.com To: Repeater-Builder@yahoogroups.comOther Sent: Tuesday, August 03, 2010 1:17 AM Subject: [Repeater-Builder] Desoldering MSR2000 RX PCB A recent thread discussed a problem disassembling a MSR2000 continuous duty PA. That triggers this query: Does anyone know if Motorola used a higher temperature solder on the MSR2000 units? My reason for asking is that this past weekend I had a hard time removing three leaky electrolytic capacitors from a MSR2000 VHF receiver board. I ended up using a 45 watt soldering pencil, which I only use for stubborn jobs, but even it had a very hard time melting the solder on the positive leads and didn't do anything for the leads soldered to ground. I've never experienced this before on a PCB. In fact the 45 watt pencil usually works well on double-sided PCBs with small to moderate groundplanes, although I'll be the first to admit that it doesn't have enough heat to handle really massive groundplanes found on some industrial PCBs. I've replaced components on many a Micor and Mitrek mobile using my 15 and 20 watt soldering pencils without a problem, so this experience came as a complete surprise. Any thoughts? 73 and aloha, Eric KH6CQ Yahoo! Groups Links
Re: [Repeater-Builder] Narrowbanding
That may be what the mask specifies. I have seen the curve plots of the mask. Now run the numbers and see what kind of signal levels that really equates to when the DTV station is running say 1 MW. It looks pretty on paper, it's not so pretty in the real world. - Original Message - From: Glenn Little WB4UIV glennmaill...@bellsouth.net To: Repeater-Builder@yahoogroups.com Sent: Monday, August 02, 2010 11:23 PM Subject: Re: [Repeater-Builder] Narrowbanding I do not know about Nextel, but, the US DTV signal fits into a 6 MHz bandwidth. We use a mask filter to ensure that the bandwidth is no more than 6 MHz. 500 kHz from band edge = -47 dB 6 MHz from band edge = -110 dB 73 Glenn WB4UIV At 10:58 AM 8/2/2010, you wrote: On 8/2/2010 10:45 AM, Scott Zimmerman wrote: I was wondering about that myself. The bandwidths spec'd just didn't seem to compute in my feeble mind. Scott Scott Zimmerman Amateur Radio Call N3XCC 474 Barnett Road Boswell, PA 15531 Jeff DePolo wrote: Florida Repeater Coordinator proposes narrowbanding: http://www.florida-repeaters.org/FRC%202meter%20narrowband%20p olicy%20released%207-18-10.pdf Apparently Carson's Rule works different in Florida than it does everywhere else. --- Jeff WN3A Course, wiki says Carson's rule is of little use in spectrum planning anyway...(http://en.wikipedia.org/wiki/Carson_bandwidth_rule). These must be the same people that think Nextel's iDen 6:1 TDMA format fits in a 25 KHz channel, or that think the US DTV standard fits in a 6 MHz channel...NOT! Yahoo! Groups Links Yahoo! Groups Links
Re: [Repeater-Builder] showing our age (old HT's)
GE PR36, shudder! A brick with wires that easily broke when the case was opened or shut. Not a nice radio to have on the bench. I ran a Portamobile 1 on 52.525 about 10 years ago, guess I'll have to dig it out of the storage and see what shape it's in these days. Moving slightly off topic, I recently came across a Motorola mobile mic with the cast metal housing. A real favorite of the cops back in the day; it had many uses, only one of which had anything to do with communicating via voice. Other uses had to do with communicating, but were more non-verbal in nature and directed at the jerk in the back seat of the cruiser. Milt N3LTQ - Original Message - From: La Rue Communications To: Repeater-Builder@yahoogroups.com Sent: Tuesday, July 27, 2010 7:16 PM Subject: Re: [Repeater-Builder] showing our age (old HT's) How about a GE PR 36? Does that qualify for old? (Esentially I think anything in our two-way museum that we're getting set up eventually qualifies as old) :-) Nice thing about the older gear - is that its SO hardy! Incredible that some of the stuff we have thats old and obsolete still works and works well! Whereas a lot of newer gear, if it got to be as old as the old stuff would be worthless and junked as forever inoperable! John Hymes La Rue Communications 10 S. Aurora Street Stockton, CA 95202 http://tinyurl.com/2dtngmn - Original Message - From: Captainlance To: Repeater-Builder@yahoogroups.com Sent: Tuesday, July 27, 2010 4:02 PM Subject: Re: [Repeater-Builder] showing our age (old HT's) Wow.. memories... A Link 50UFS low band base station.. We have one here, too... Still works. Lance N2HBA - Original Message - From: La Rue Communications To: Repeater-Builder@yahoogroups.com Sent: Tuesday, July 27, 2010 4:20 PM Subject: Re: [Repeater-Builder] showing our age (old HT's) I think I automatically disqualify myself since I dont know too much about our units. But one of the cornerstone pieces of our shop is our Link Repeater. Im not trying to one up anyone - but rather share and get into the OLD stuff with the rest of ya. I also dont think I qualify because I grew up on CHiPs and Dukes of Hazard. :) So overlook that little fact and let me ask if anyone has dabbled with this machine? (See attached) John Hymes La Rue Communications 10 S. Aurora Street Stockton, CA 95202 http://tinyurl.com/2dtngmn - Original Message - From: John Gleichweit To: Repeater-Builder@yahoogroups.com Sent: Tuesday, July 27, 2010 12:04 PM Subject: Re: [Repeater-Builder] showing our age (old HT's) Whaddaya mean lunchboxes don't count? I have a pair of GE Portamobile II's in the shop just begging to be recrystalled and ready to rock. If course, I was considering building those into APRS trackers or packet boxes, where everything was built inside, and all you needed to do was plug in a laptop. I dug an actual GE HandiTalkie out of the bottom of a box that was full of surplus stuff from the county. In that same lot was a couple of MX300s. -- John Smokey Behr Gleichweit FF1/EMT, CCNA, MCSE IPN-CAL023 N6FOG UP Fresno Sub MP183.5 ECV1852 List Owner x10, Moderator x9 CalEMA 51-507 http://smokeybehr.blogspot.com http://www.myspace.com/smokeybehr - Original Message From: skipp025 skipp...@yahoo.com To: Repeater-Builder@yahoogroups.com Sent: Sun, July 25, 2010 7:00:36 PM Subject: [Repeater-Builder] showing our age (old HT's) Allow me to show my age ... To me, the HT-220 is/was a Xtal Controlled Ht !! Allow me to show my age... The HT here is a VHF Engineering 2 Meter Portable assembled from a kit... and it still works. :-) s. ps: Surplus Motorola and GE Lunch Boxes don't count on the bragging scale. Yahoo! Groups Links
Re: [Repeater-Builder] Re: Duplxer, tuned cavity question.
OK, too much interperatation based on a lack of information. For 2 antennas you need vertical seperation (best) or horizantal seperation (very large), or 2 bandpass filters, one for each transceiver. Easiest solution, if you have the vertical real estate, use at least 25-30 ft seperation (preferably 40-50ft) between the antennas. I prefer to use top of lower antenna to bottom of top antenna as the measurement of distance. Charts often say center of antenna radiation. Horizontal seperation would require 300' for the same amount of isolation. Next best is a lesser amount of vertical seperation, coupled with bandpass cavities. See http://www.repeater-builder.com/antenna/separation.html I would suggest that you find a local elmer to assist you. Milt N3LTQ - Original Message - From: Kc7hgn kc7...@yahoo.com To: Repeater-Builder@yahoogroups.com Sent: Tuesday, July 20, 2010 5:59 AM Subject: [Repeater-Builder] Re: Duplxer, tuned cavity question. Well they don't have to be on the same antenna. But each one would be about 25 feet from each other. Both Copper J-Pole antennas. I guess I would still need to buy a duplexer. Could I build one? Will be 50w on 1 antenna and 25 on the other. I don't know much about this stuff. Thanks, Kevin Kc7hgn --- In Repeater-Builder@yahoogroups.com, Joe k1ike_m...@... wrote: Good advice. The only thing that I would add is that you need to use good quality equipment for the antenna system. This includes the duplexer, jumpers, connectors, cable and antenna. When you have a situation where two transmitters can be on the air at the same time on the same antenna system, you always stand the chance of creating intermod. 73, Joe, K1ike On 7/19/2010 6:55 AM, Milt wrote: Assuming from reading between the lines that you want to use both stations on the same antenna, get a 2 meter duplexer. The seperation between the 2 frequencies is 0.64 MHz. At bare minimum you need a notch (reject) duplexer but a bandpass-band reject type would probably be the better choice. Tune each leg to the respective frequency and connect to the respective radio. Milt N3LTQ - Original Message - From: Kc7hgnkc7...@... To:Repeater-Builder@yahoogroups.com Sent: Monday, July 19, 2010 5:48 AM Subject: [Repeater-Builder] Duplxer, tuned cavity question. I have an APRS station on 144.39. I would also like to run my Packet station on 145.03. So I need someway to run both stations. What would I need to do? Can I build what I would need? If so where would I find that info? Thanks, Kevin Kc7hgn Yahoo! Groups Links Yahoo! Groups Links
Re: [Repeater-Builder] Duplxer, tuned cavity question.
Assuming from reading between the lines that you want to use both stations on the same antenna, get a 2 meter duplexer. The seperation between the 2 frequencies is 0.64 MHz. At bare minimum you need a notch (reject) duplexer but a bandpass-band reject type would probably be the better choice. Tune each leg to the respective frequency and connect to the respective radio. Milt N3LTQ - Original Message - From: Kc7hgn kc7...@yahoo.com To: Repeater-Builder@yahoogroups.com Sent: Monday, July 19, 2010 5:48 AM Subject: [Repeater-Builder] Duplxer, tuned cavity question. I have an APRS station on 144.39. I would also like to run my Packet station on 145.03. So I need someway to run both stations. What would I need to do? Can I build what I would need? If so where would I find that info? Thanks, Kevin Kc7hgn Yahoo! Groups Links
Re: [Repeater-Builder] Controller recommendations
Steve, How do you propose to operate the Quantar in analog mode with the external controller and simultaniously in digital mode using the internal controller? The Quantar can operate as a mixed mode repeater ( analog to analog and digital to digital) but only with the internal controller function. - Original Message - From: Steve Jones To: Repeater-Builder@yahoogroups.com Sent: Friday, July 16, 2010 1:25 PM Subject: Re: [Repeater-Builder] Controller recommendations I forgot two items which will affect my choice: 1) Control codes cannot contain the DTMF codes A,B,C or D since I don't have a radio with the full 4x4 keypad. 2) The Quantar will probably have to be left setup as a repeater in order to pass the P25. The controller would only need to key the repeater for link audio and repeater messages. -- Steve steve.jones at rogers.com
Re: [Repeater-Builder] Re: help and suggestions interference issues
Paul, If I read your message correctly you had the receiver set to open on PL only. Had you tried using PL AND CSQ (also called AND squelch) as the opening requirement? Milt N3LTQ - Original Message - From: paul_k6eh paulmetz...@hamradio-dv.org To: Repeater-Builder@yahoogroups.com Sent: Monday, July 05, 2010 8:37 AM Subject: [Repeater-Builder] Re: help and suggestions interference issues Actually, with regards to a D-DSTAR signal opening up an analog receiver set to decode only PL, it can happen. I had an analog repeater (Motorola) co-channeled with a D-STAR repeater. The users of the D-STAR repeater would in fact open up my repeaters receiver and pass through. I'm trying to recall what the PL was that that I had used before I had to change it (thanks to D-STAR). It was either 100.0 or 123.0 . So in short, Yes a D-STAR signal can open up an analog receiver set to decode PL. Also, if your still looking for a recording of D-STAR transmission (both raw and decoded), you may find them at http://www.hamradio-dv.org . Paul Metzger - K6EH Trustee of the N6DVA Mototrbo Amateur Radio Repeater --- --- In Repeater-Builder@yahoogroups.com, Doug Hutchison specialq@... wrote: Yes Doug, Sent a recording off list but you have I think hit the nail on the head as am sure CTCSS is not applicable to D-Star as you say. A strong D-Star signal would get into the RX though, despite CTCSS, I think but cannot prove it as no D-Star here. Doug - GM7SVK Yahoo! Groups Links
Re: [Repeater-Builder] Help Needed (Guidance and advice) tuning a DB Products Duplexer
Josh, Ed's description for tuning is right on the money. I would try moving the unit just a slight bit to get used to how it tunes before trying to move it over such a wide frequency range. Once you are comfortable with your equipment and how the duplexer tunes, then move it to the new amateur frequency. Milt N3LTQ - Original Message - From: Ed Yoho w6yj_ya...@67hz.net To: Repeater-Builder@yahoogroups.com Sent: Saturday, May 29, 2010 12:09 AM Subject: Re: [Repeater-Builder] Help Needed (Guidance and advice) tuning a DB Products Duplexer Josh wrote: Ok so here's what I've got (I think) http://www.n2ckh.com/FORSALE/REPEATERS/DUPLEXERS/DB4076/DSC02678.JPG Hamvention special, 4 cavities, appears to be a DB Products 4076 family unit. My bench tools: HP 8924c w/ Spec Analyzer and Tracking Generator. My problem - existing set of cans is tuned for 460~mhz. I need to bring them down to 443/448.It was my understanding that they would have dual adjustments - one for setting the band pass frequency, one for setting the reject frequency. Sounds simple. Except under the 'covers' there is nothing else to adjust... So are they just single frequency pass or notch filters? So thats the first question - The second question is - ok , so if they're just single frequency filters, why can't I spin them 'into the right range' as easily as I thought I'd be able to do I've tuned a couple of motorola micor filters on the spec analyzer in the last couple of days, mostly made sense and was smooth as silk... However, after messing with the first can, I'm confused. Moving the adjustment certainly changes the properties of the notching - but it didnt really move the bandpass around... It mostly changed the shape and depth of the notching - not the frequency. What knowledge am I missing - I'm an amateur :) Yes I've seen the 'how to tune db products duplexor' doc - but it talks about dual controls, which apparently I don't have. Did I buy a piece of junkola? Teach me obie-wan. j Josh, The large nut tipped rods in the center of each cavity are the pass adjustments. Loosen the locking nut at the bottom of each tuning rod and turn the shafts clockwise to set the pass responses where you want. Be sure to keep them set high and low as they are labeled. Once the pass is where you want it, tighten the clamp nuts back down. Then remove the small round covers between the N connectors on each cavity and use a small screwdriver or metal tipped tuning tool to _carefully_ put the notches where they belong. Put the covers back on and enjoy. Be sure to put a termination on the side you are not tuning. Ed Yoho W6YJ Yahoo! Groups Links
Re: [Repeater-Builder] OT Looking for service manual Kenwood TM-733A
Thank you Mike, but that scan is the instruction manual not the service manual. Milt N3LTQ - Original Message - From: Mike Morris wa6i...@verizon.net To: Repeater-Builder@yahoogroups.com Sent: Thursday, May 20, 2010 12:54 PM Subject: Re: [Repeater-Builder] OT Looking for service manual Kenwood TM-733A At 08:10 AM 05/20/10, you wrote: Looking for service manual for the TM-733A radio in paper(preferred)or electronic format. B51-8264-00 original or B51-8264-10 revised Document is NLA from Kenwood Thanks Milt N3LTQ Google is your friend. I typed in the following and found four sources in 2 minutes. kenwood tm-733 manual I put the best/clearest of the four on the Kenwood page at repeater-builder. It's a 13.8 MB download. Mike WA6ILQ Yahoo! Groups Links
Re: [Repeater-Builder] uniden aru 251k
Gary, The Uniden ARU-251K is a 450-470 MHz CRYSTAL based repeater/base station with a very limited internal controller. If it can be dropped into the 440 ham band you will then need an external controller. The standard duplexer with the unit is a simple notch type which may be suitable for operation on an isolated site but will be nothing but problems on a crowded one. The first thing to do is to check the repeater on the frequency that it is currently set up for and determine if it is working properly. After that with a service manual and the proper test equipment and a new set of crystals you may be able to move it into the ham bands. Milt N3LTQ - Original Message - From: ke5...@yahoo.com To: Repeater-Builder@yahoogroups.com Sent: Tuesday, May 18, 2010 8:24 PM Subject: [Repeater-Builder] uniden aru 251k I have this repeater and I need the modification for 440 amateur use. Any help on this will be appreciated. Thanks in advance. Gary Sent from my Verizon Wireless BlackBerry -- From: MCH m...@nb.net Date: Tue, 18 May 2010 20:17:14 -0400 To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Sinclair dipole phasing harness I can't speak specifically of Sinclair, most all of the models I've used will do either omni or cardioid by moving the elements. The spacing from the mast stays the same. Joe M. Nate Duehr wrote: On 5/18/2010 12:29 PM, Larry Horlick wrote: I suspect that the harness does not affect the pattern, but rather it is the dipole to mast spacing. Yes, I believe this is correct. Whenever I've looked, notice that the omni versions are 1/2 wave spacing from the mast, and the cartioid are 1/4 wave spacing from the mast, in almost all of Sinclair's product line. Nate WY0X
Re: [Repeater-Builder] How About This One?
Attenuator out of a Mocom 70 UHF control station. - Original Message - From: La Rue Communications To: Repeater-Builder@yahoogroups.com Sent: Tuesday, May 11, 2010 1:31 PM Subject: [Repeater-Builder] How About This One? Not sure what this is either. The part numbers turn up nothing in google. Not sure if its even a Motorola product. Has no Moto stamping. Might be something else that someone may be familiar with. The number on the side thats etched in reads 15B84073D01. Thanks for your help! John Hymes La Rue Communications 10 S. Aurora Street Stockton, CA 95202 http://tinyurl.com/2dtngmn
Re: [Repeater-Builder] Neat kit for switching repeater devices
Eric, The power supply on the RKR and GR series repeaters has a switch which controls the action of the fan. It can either be thermally controlled or run constantly. Milt N3LTQ - Original Message - From: Eric Lemmon wb6...@verizon.net To: Repeater-Builder@yahoogroups.com Sent: Saturday, May 01, 2010 11:04 PM Subject: RE: [Repeater-Builder] Neat kit for switching repeater devices Larry, That's odd; both the GR1225 and RKR1225 repeaters I am familiar with, which use the R1225 transceiver, have a small thermal switch that is wedged between two of the heat-sink fins. In both repeaters, the fan runs only when the radio gets hot. I am surprised that you have a repeater using the R1225 in which the fan runs continuously. Perhaps this installation is a prime candidate for a thermal switch! 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Larry Horlick Sent: Saturday, May 01, 2010 7:13 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Neat kit for switching repeater devices This is excellent Eric. I have an R1225 repeater in a GR500 case. There is a fan but it runs continuously. The duty cycle is low but because of the nature of the service there are times when it may be very high for extended periods of time. So most of the time the fan is not needed, but I want it there for those rare occasions. I don't recognize the part no. on the fan it looks remarkably similar to the one stock in GR500. This will work very well for me. Thanks. lh On Sat, May 1, 2010 at 8:28 PM, Eric Lemmon wb6...@verizon.net mailto:wb6...@verizon.net wrote: Larry, My first use of this thermal switch was on a solar-powered Motorola R1225 UHF repeater at a commercial site. I simply drilled and tapped two 4-40 holes on a flat portion of the outside fin, and mounted the thermal switch after applying some heat-conductive paste. I used a three-inch low-EMI Panasonic fan blowing right on the fins. This is a 45-watt repeater set for about 30 watts output. It went into service early in 2003, and has been trouble-free ever since. I have attached a picture of what it looks like. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com [mailto:Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com ] On Behalf Of Larry Horlick Sent: Saturday, May 01, 2010 11:56 AM To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Subject: Re: [Repeater-Builder] Neat kit for switching repeater devices Eric, This is good info. I have an immediate use for this. How have you actually attached this 'stat to the fin? Larry On Sat, May 1, 2010 at 2:36 PM, Eric Lemmon wb6...@verizon.net mailto:wb6fly%40verizon.net mailto:wb6...@verizon.net mailto:wb6fly%40verizon.net wrote: Scott, I must agree that the CK1614 is an extremely versatile timer, with many potential uses. However, using it for fan control is not only expensive, but unnecessary. A fan blowing on a transmitter heat sink does absolutely nothing immediately after the transmitter is keyed, since the heat sink is likely at ambient temperature. It takes a period of time for the heat sink to warm up, so operating the fan prematurely is a waste of energy- which may be an issue for a solar-powered repeater. IMHO, the most efficient means of fan control is also the cheapest: A thermal switch. My first choice is a Cantherm #R2005015 normally-open thermostat that closes at 50 degrees Celsius, about 122 degrees Fahrenheit. When attached to a heat-sink fin, it turns the fan on when necessary, and keeps it on until the heat sink cools below about 100 degrees F- around body temperature. This particular switch is available from Digi-Key for about $9, as Catalog Number 317-1094-ND. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com mailto:Repeater-Builder%2540yahoogroups.com [mailto:Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com mailto:Repeater-Builder%2540yahoogroups.com ] On Behalf Of na4it Sent: Saturday, May 01, 2010 9:38 AM To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com mailto:Repeater-Builder%2540yahoogroups.com Subject: [Repeater-Builder] Neat kit for switching repeater devices I have started using this little kit (http://www.electronickits.com/kit/complete/elec/ck1614.htm http://www.electronickits.com/kit/complete/elec/ck1614.htm http://www.electronickits.com/kit/complete/elec/ck1614.htm http://www.electronickits.com/kit/complete/elec/ck1614.htm http
Re: [Repeater-Builder] Neat kit for switching repeater devices
The original GR1225 power supply was a linear Astron SL-14M good for 7A continuous and 14A @ 20% duty cycle. It had 2 molex connectors on the back, one for the high current DC and the other, a 6 pin, for the fan. The current product is HPN9033A a Duracomm RP-15 switcher with a high current pigtail and a second pigtail for the fan. THese have the switch just below the pigtails that either runs the fan constantly or follows the thermal switching. Milt N3LTQ - Original Message - From: Larry Horlick To: Repeater-Builder@yahoogroups.com Sent: Monday, May 03, 2010 9:21 AM Subject: Re: [Repeater-Builder] Neat kit for switching repeater devices What is the Moto part no. of the ps to which you refer? lh On 5/3/10, Milt men...@pa.net wrote: Eric, The power supply on the RKR and GR series repeaters has a switch which controls the action of the fan. It can either be thermally controlled or run constantly. Milt N3LTQ - Original Message - From: Eric Lemmon wb6...@verizon.net To: Repeater-Builder@yahoogroups.com Sent: Saturday, May 01, 2010 11:04 PM Subject: RE: [Repeater-Builder] Neat kit for switching repeater devices Larry, That's odd; both the GR1225 and RKR1225 repeaters I am familiar with, which use the R1225 transceiver, have a small thermal switch that is wedged between two of the heat-sink fins. In both repeaters, the fan runs only when the radio gets hot. I am surprised that you have a repeater using the R1225 in which the fan runs continuously. Perhaps this installation is a prime candidate for a thermal switch! 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Larry Horlick Sent: Saturday, May 01, 2010 7:13 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Neat kit for switching repeater devices This is excellent Eric. I have an R1225 repeater in a GR500 case. There is a fan but it runs continuously. The duty cycle is low but because of the nature of the service there are times when it may be very high for extended periods of time. So most of the time the fan is not needed, but I want it there for those rare occasions. I don't recognize the part no. on the fan it looks remarkably similar to the one stock in GR500. This will work very well for me. Thanks. lh On Sat, May 1, 2010 at 8:28 PM, Eric Lemmon wb6...@verizon.net mailto:wb6...@verizon.net wrote: Larry, My first use of this thermal switch was on a solar-powered Motorola R1225 UHF repeater at a commercial site. I simply drilled and tapped two 4-40 holes on a flat portion of the outside fin, and mounted the thermal switch after applying some heat-conductive paste. I used a three-inch low-EMI Panasonic fan blowing right on the fins. This is a 45-watt repeater set for about 30 watts output. It went into service early in 2003, and has been trouble-free ever since. I have attached a picture of what it looks like. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com [mailto:Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com ] On Behalf Of Larry Horlick Sent: Saturday, May 01, 2010 11:56 AM To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Subject: Re: [Repeater-Builder] Neat kit for switching repeater devices Eric, This is good info. I have an immediate use for this. How have you actually attached this 'stat to the fin? Larry On Sat, May 1, 2010 at 2:36 PM, Eric Lemmon wb6...@verizon.net mailto:wb6fly%40verizon.net mailto:wb6...@verizon.net mailto:wb6fly%40verizon.net wrote: Scott, I must agree that the CK1614 is an extremely versatile timer, with many potential uses. However, using it for fan control is not only expensive, but unnecessary. A fan blowing on a transmitter heat sink does absolutely nothing immediately after the transmitter is keyed, since the heat sink is likely at ambient temperature. It takes a period of time for the heat sink to warm up, so operating the fan prematurely is a waste of energy- which may be an issue for a solar-powered repeater. IMHO, the most efficient means of fan control is also the cheapest: A thermal switch. My first choice is a Cantherm #R2005015 normally-open thermostat that closes at 50 degrees Celsius
Re: [Repeater-Builder] MT1000 DTMF programming
Make sure that you have DTMF fronts and not selectable MDC1200 fronts, IIRC they looked pretty much alike. The MDC ones had a protrusion at the top while the DTMF ones did not. Milt N3LTQ - Original Message - From: brown7...@bellsouth.net To: Repeater-Builder@yahoogroups.com Sent: Monday, April 26, 2010 12:05 PM Subject: [Repeater-Builder] MT1000 DTMF programming I have taken up programming MT1000's. I am having trouble getting some radios that have DTMF to accept the fronts. I have several different model fronts and have tried them all to no avail. Is there a specific procedure to get the control module to recognize the DTMF front? I continually get the message this radio front incapable of DTMF. Sometimes the program version R03.01.02 states that a model ntn5697A front must be used. That is an encode/decode front and hard to come by. As I understand it, these radios should still be able to use the other fronts. I have tried the continuous and short burst fronts with the same results. Can anyone help me with this issue? Thanks...Ray Yahoo! Groups Links
Re: [Repeater-Builder] 3' motorola or GE cabinet wanted.
Go visit your local two-way shops, chances are they have some. Milt N3LTQ - Original Message - From: rush8001 unidens...@hotmail.com To: Repeater-Builder@yahoogroups.com Sent: Monday, April 26, 2010 2:47 PM Subject: [Repeater-Builder] 3' motorola or GE cabinet wanted. I've been looking around for a short cabinet, and can't seem to find what I'm looking for. The MSR2000 cab I have is not deep enough for my repeater project. If anyone has anything they want to get rid of in the CT area, contact me off list. Thanks!! Yahoo! Groups Links
e: [Repeater-Builder] Re: Pager Interference Revisited
Mike, Does the interfering signal come and go or is it constant? Does it have any AC component; ie buzz or hum at 60Hz, 120Hz, etc., or any raw buzzing noise? Are there any broiadcast TV stations in the area, DTV or LP translators? Is the UHF pager signal analog, digital or both? What test equipmet do you ahve available? Is the repeater in a poplulated area or remote? Milt N3LTQ - Original Message - From: Mike Besemer (WM4B) To: Repeater-Builder@yahoogroups.com Sent: Saturday, April 24, 2010 3:36 PM Subject: RE: [Repeater-Builder] Re: Pager Interference Revisited I don't think so, Chuck. I work on Robins and traverse it pretty much from end-to-end daily. I also have to traverse it quite a ways just to get off of it to go foxhunt this beast. Generally the signals on-base are weak to non-existent. It's bloody amazing how much RF crap is in the air. Using a Google Earth application I can see zillions of sites within earshot. The mixing possibilities are endless! I'm somewhat surprise that we've never heard any audio mixing in with it. 73, Mike WM4B From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Chuck Kelsey Sent: Saturday, April 24, 2010 3:16 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: Pager Interference Revisited How close is Robins AFB? Maybe? Chuck WB2EDV - Original Message - From: Mike Besemer (WM4B) To: Repeater-Builder@yahoogroups.com Sent: Saturday, April 24, 2010 2:48 PM Subject: RE: [Repeater-Builder] Re: Pager Interference Revisited Given that the interference is in three different repeaters over about 40 air-miles, I have not done that. I've THOUGHT about it, but it didn't make sense, give the circumstances. 73, Mike WM4B
Re: [Repeater-Builder] Re: Pager Interference Revisited
OK, this is probably not going to be an easy one. I have seen several instances of mast-mounted TV preamps oscillating and acting as miniature transmitters capable of sweeping over wide swaths of spectrum as the temperature changes. They usually exhibit a raw AC buzz on the signal. They are almost never active when the weather is cold, only coming active as the ambient temperature rises. Usually were fed with twin lead. Your description of the audio seems to put that possibility pretty far down the list. At this point I would probably want to look at the incoming signals on the repeater with a spectrum analyser and see if you can quantify the level of the incoming interference signals. If the interference level is high enough you should be able to hear it and maybe track it with a service monitor that can be run off of 12v in a mobile. Since you can call a number on one of the transmitters you can control things a bit. Good luck hunting. Milt - Original Message - From: Mike Besemer (WM4B) To: Repeater-Builder@yahoogroups.com Sent: Saturday, April 24, 2010 4:42 PM Subject: RE: [Repeater-Builder] Re: Pager Interference Revisited Milt, Not sure what you mean by 'come and go'. It's there when the pager transmitter is up, gone when it's not. It also comes and goes with heat and sun. we may have days with no interference if it's cool and cloudy or just plain cold. Rain makes no difference. Nothing remarkable about the audio. sounds like clean, clear paging tones. Never heard anything els There is an abundance of TV stations, DTV, translators, AM, FM. you name it. The paging signals are both, depending on which site it's coming from. I can get my hands on pretty much anything I need. Spectrum analyzer is no problem. I have a good 'connection'. Did some hunting with a spectrum analyzer last year to no avail, but now that I have the ability to call the system and have it send out a page we have a little better advantage. I'd call the area 'populated', but not 'urban'. Mostly housing around the site, but plenty of industry (and towers) visible from the top of the water tank. (We are, by the way, the only user on the tank.) From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Milt Sent: Saturday, April 24, 2010 4:19 PM To: Repeater-Builder@yahoogroups.com Subject: e: [Repeater-Builder] Re: Pager Interference Revisited Mike, Does the interfering signal come and go or is it constant? Does it have any AC component; ie buzz or hum at 60Hz, 120Hz, etc., or any raw buzzing noise? Are there any broiadcast TV stations in the area, DTV or LP translators? Is the UHF pager signal analog, digital or both? What test equipmet do you ahve available? Is the repeater in a poplulated area or remote? Milt N3LTQ - Original Message - From: Mike Besemer (WM4B) To: Repeater-Builder@yahoogroups.com Sent: Saturday, April 24, 2010 3:36 PM Subject: RE: [Repeater-Builder] Re: Pager Interference Revisited I don't think so, Chuck. I work on Robins and traverse it pretty much from end-to-end daily. I also have to traverse it quite a ways just to get off of it to go foxhunt this beast. Generally the signals on-base are weak to non-existent. It's bloody amazing how much RF crap is in the air. Using a Google Earth application I can see zillions of sites within earshot. The mixing possibilities are endless! I'm somewhat surprise that we've never heard any audio mixing in with it. 73, Mike WM4B From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Chuck Kelsey Sent: Saturday, April 24, 2010 3:16 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: Pager Interference Revisited How close is Robins AFB? Maybe? Chuck WB2EDV - Original Message - From: Mike Besemer (WM4B) To: Repeater-Builder@yahoogroups.com Sent: Saturday, April 24, 2010 2:48 PM Subject: RE: [Repeater-Builder] Re: Pager Interference Revisited Given that the interference is in three different repeaters over about 40 air-miles, I have not done that. I've THOUGHT about it, but it didn't make sense, give the circumstances. 73, Mike WM4B
Re: [Repeater-Builder] Motorola Radius P50
If he was thinking 2 screwdrivers he was not thinking about the P50; the Spirit perhaps but not the P50. Milt - Original Message - From: MCH m...@nb.net To: Repeater-Builder@yahoogroups.com Sent: Friday, April 09, 2010 3:11 PM Subject: Re: [Repeater-Builder] Motorola Radius P50 But, how many people know that? I think his point was that it doesn't seem to have been played with by someone who didn't know at least somewhat what they were doing. I've seen some of those come in. Joe M. Bill Smith wrote: Pry marks? Pop out the two clips in the battery compartment and pull up on the antenna. No prying needed! :-) Doesnt appear to be tampered with or pry marks indicating it was opened before. (Thank goodness). Yahoo! Groups Links
Re: [Repeater-Builder] DB-225
Tim, You have two different antennas. The antenna you describe as the 225 is a directional antenna. It consists of a driven element and a reflector. The pipe you describe is used to secure the mounting clamps. I believe this antenna wants to be mounted so that the tower leg extends above and below the antenna. The pattern will be a cardoid with a distinct null. Try to find an older (late 1990's) Decibel Products catalog. Much good information is stored in these old books. The second antenna you describe sounds like a DB-212. It mounts directly to the tower and want's to see tower leg above and below the antenna. This one produces an almost omni pattern with a slight cardoid null. Go to http://www.repeater-builder.com/antenna/ant-sys-index.html about 3/4 of the way dow the page you will find references to the DB-212 antenna and this link http://www.repeater-builder.com/db/pdfs/db-212-catalog-sheet-(andrew).pdf along with several others. Milt N3LTQ - Original Message - From: Tim Ahrens tahr...@swtexas.net To: Repeater-Builder@yahoogroups.com Sent: Wednesday, April 07, 2010 2:43 PM Subject: Re: [Repeater-Builder] DB-225 Hi Chuck... Looks like I have two different versions of it. The one that is marked 225 has a square aluminum box that the element pieces fit into. The driven side is farthest away from the tower. It has a short (10) piece of pipe attached to it that would fit into one of the standard tower mount attachments. The second type - also marked DB products, but I can't read the type, has the element pieces attached to a cast aluminum piece. The driven side is closed to the tower, an will also be about 7 from the tower. You could attach the casting to a piece of pipe with clamps. Tim Yahoo! Groups Links
Re: [Repeater-Builder] Motorola Syntor system 9000 X help?
Aaron, Let's start out by determining what your desired end result is. The listing shows several additional items that may or may not be used or useful. The basic radio as seen in the listing is a 32 mode radio in VHF high band 150-174 MHz. A mode can be thought of as a channel in the radio but it consists of the information that defines how the radio is to operate including: transmit frequency, the receive frequency, the transmit CTCSS (if used), the receive CTCSS (if used), and scan information. Therefore each set of definitions make up the operational mode of the radio when the definition set (mode) is selected. The radio is programmed using a software package, an interface cable and programming interface (RIB box). The software has 2 componet programs; one programs the radio, the other programs the control head. Accessories were interfaced using a feedthru connector called a T-connector. Moving to more modes (channels) involves replacing two IC's, one in the radio, one in the control head and reprogramming. The expansion allows the radio to access up to 64 modes. A variation existed to allow 128 modes but this required a change of the firmware (another chip programmed with what is in essance the radio's operating system) in the control head. This upgrade is no longer available. As for the 255 mode modifications, I have heard about them but never seen a radio so equipped. The 255 mode modifications were not factory. YMMV. Special Product variations are often available for commercial equipment, especially where it is used in public safety applications. These SP product have limited documentation and in recent years often use special programming software that often never finds it's way past the original user. Assuming that you are a ham there is a version of the software that is available the allows the radio to operate in the 2 meter ham band. Use of the PA/siren box requires a siren driver capable of handling 100 watts of audio power. Unless you have a legitimate need for a mobile PA, I suggest removing it and programming it out of the radio. It can be removed with no problems, there will be brief display of an error shown when the radio powers up but it will not prevent basic radio operation. The other radio (Spectra) used a different control head protocol than the Syntor X9000, although the later HCN1073 control heads could be used with either radio after returning the control head to Motorola for special reprogramming. If it was part of the package then this is an SP package system. Good luck. SP packages can be rewarding or a source of headaches. Milt N3LTQ - Original Message - From: AARON LEWIS DINKIN To: undisclosed-recipients: Sent: Saturday, April 03, 2010 12:46 AM Subject: [Repeater-Builder] Motorola Syntor system 9000 X help? Motorola Syntor system 9000 X help? Salutations, I just recently acquired a Motorola Syntor 9000 X (as well as a Systems 9000 kit as well as a Spectra box) off eBay, and I'm in a bit of a pickle; I didn't realize how much of a radio I was getting myself into, because I only have previous HT (Yaesu VX-8R and Kennwood K2AT) experience, and I didn't realize how HEAFTY the Motorola was going to be. The Connector cables alone are so massive and confusing, I'm reaching out for help. I'm going to need someone to help me sort through all of the information from http://www.onfreq.com/syntorx/ as well as http://www.repeater-builder.com/motorola/syntor/syntor-index.html to help me sort through and reach a boiled down meat and potatoes step by step sequence I can go through to help trouble shoot the radio and HOOK IT UP TO MY VEHICLE. I've noticed the above sites recommend that I open up the radio to see if it's setup for a positive or a negative ground. But i really need help decoding the cables so I know what wires go where? I need to decode which wires are for the SIREN, the LIGHT BAR, the Vehicle power, etc. I'm also curious: The Syntor X9000 followed the Syntor X and is the same radio from an RF standpoint, but the internal controller board was upgraded to expand the number of memory channels up to 255. The control cable connector on the X9000 is the same as the X, but the accessories are not compatible. The X9000 uses Systems 9000 accessories and options that communicate with the radio via a 9600 baud serial bus. The control head(s) are smart heads with their own microprocessor inside. Unlike the Syntor X the X9000 is programmed with RSS (and a slow PC), a RIB and special adapter cable that goes in series with the normal radio cable. The the special cable is not an absolute requirement; there are several ways to make your own connection from a radio to a RIB. In other words, the X9000 is a more desirable mobile radio than a Syntor X since you don't need the almost-impossible-to-find suitcase programmer for the plain Syntor
Re: [Repeater-Builder] Nice article on the Molotora Gontor
Order from your local Molotora dealer at 00:01 on April 1 only. Orders will be filled by donkey cart. If you receive your order within 1 year you will be required to pay additional fees. Milt N3LTQ v - Original Message - From: Scott Zimmerman n3...@repeater-builder.com To: Repeater-Builder@yahoogroups.com Sent: Thursday, April 01, 2010 8:46 AM Subject: Re: [Repeater-Builder] Nice article on the Molotora Gontor Nice. I like it. Interesting radio. I need to get one of those. Are they available from *any* Motorola dealer, or do you need to contact internal sales directly at 1-800-422-4210 and ask for it specifically? Scott Scott Zimmerman Amateur Radio Call N3XCC 474 Barnett Road Boswell, PA 15531 Kevin Custer wrote: Bob Meister has written a nice article on the Molotora Gontor for RB. http://www.repeater-builder.com/molotora/gontor/gontor.html Thanks go out to Bob for his efforts! Kevin Custer Yahoo! Groups Links Yahoo! Groups Links
Re: [Repeater-Builder] Exciter Filter in a UHF MSR2000 Station
Eric, The adjustments for FL101 are very easy to access and are not at all hidden. The problem most likely lies in the physical size of the filter which will limit it's low end performance. The exciter tuning chart in the 68P81061E55 service manual shows the low end of the range at 440MHZ. The same manual indicates models made to cover the 450-512 MHz range but nothing below these ranges. Interestingly enough the UHF manual is a supplement to the VHF service manual 68P81061E50. I'll defer to Skip or others who have seen the MSR2000 in some of it's more unique varients. I'll send you a picture of a board direct when I get the camera hooked up. Milt N3LTQ - Original Message - From: Eric Lemmon wb6...@verizon.net To: Repeater-Builder@yahoogroups.com Sent: Monday, March 22, 2010 10:12 PM Subject: [Repeater-Builder] Exciter Filter in a UHF MSR2000 Station A recent post to this list described the inability of the bandpass filter FL101 to pass frequencies in the 70cm Amateur band. The schematic diagram in the UHF MSR2000 service manual shows the four helicals to be adjustable, but it seems that the adjustments are concealed. Inasmuch as this filter prevents many Hams from retuning their stations down to 70cm, I would like to ask anyone with a spare MSR2000 UHF bandpass filter to allow me to see if it can be retuned. My intention is to first sweep the filter on a network analyzer to see what its stock response looks like. Then, if the owner of the filter allows it, I would see what is needed to gain access to the internal adjustments, and if retuning to the 70cm band is possible. I shall endeavor to return the filter to its owner after this investigation, either tuned as it was originally or tuned to favor 70cm. As you might expect, this science project will form the basis of a how-to article in the RBTIP. I don't have a UHF MSR2000 to experiment on, so I am hopeful that someone out there may have an idle UHF MSR2000 station that can serve as a source for the FL101 filter. 73, Eric Lemmon WB6FLY Yahoo! Groups Links
Re: [Repeater-Builder] Anyone work on a Radio Specialty Mfg Mountain Top Repeater before?
Just the standard words of wisdom; be sure you verify that it works, and how it works before starting any conversion. That way you only have to deal with one problem at a time not compounded problems. Milt N3LTQ - Original Message - From: AJ To: Repeater-Builder@yahoogroups.com Sent: Wednesday, February 24, 2010 10:39 AM Subject: [Repeater-Builder] Anyone work on a Radio Specialty Mfg Mountain Top Repeater before? I have not one but two of these gems sitting in my office right now... 2 channel crystal controlled repeaters in a nice battleship grey cabinet. I believe BLM used these here in the western states for quite a long while before switching to Daniels. A factory test sheet in one of the 3 service manuals I have specifies .15 uV sensitivity at 12 dB quieting; .21 UV sensitivity at 20 dB quieting with a whopping 8 ma draw in standby, swinging to 1.8 amps in repeat. Overall looking at the design, it appears quite logically laid out. Looks like power output is around 8 watts and factory spec was 145 to 174 MHz in 1983. We're looking at rerocking it for 147 MHz as a portable repeater in a Pelican case with a Q2220 duplexer... ICM has already quoted $21 a rock with a 2 week lead time. Any one have a chance to work on one of these before?
Re: RE: [Repeater-Builder] Spectra Scan
That means that you have entered the scan programming mode...in other words your radio is programmed for Operator Selectable Scan. Pressing RCL at this point will show you what is in the scan list. Preeing HOME will exit the list. Use the SEL button to add a mode to the list (16 entries IIRC) Use the DEL button to delete a mode from the list. - Original Message - From: Mark To: Repeater-Builder@yahoogroups.com Sent: Monday, February 01, 2010 11:36 AM Subject: RE: RE: [Repeater-Builder] Spectra Scan Yep – I designated which Modes are displayed in each Zone… FWIW – this morning on the way to work (I know – I should do this while PARKED) I tried to activate SCAN again. If I hold the SCAN button down for 2 seconds, the SCAN indicator flashes and I get “SEL MODE”, so apparently the scan list is empty. ??? However, it appears the scan list is NOT Zone-dependent, since the first Mode that showed up when I tried to toggle through was one from a different Zone than the one I had selected to operate from. I wonder if I can create scan lists by Zone… Now, if I can just find the Spectra operator’s manual I have squirreled-away… ;-) Mark – N9WYS From: Repeater-Builder@yahoogroups.com On Behalf Of dmurman… I'll have to check later tonight when I get home but it is not an option but a function key on the bottom of the screen when you are in the Zones menu. Like I mentioned when I get home tonight I'll fire up the computer and give you the proper function keys to get to the scan menu. When you entered the modes did it ask for the Zone? David
Re: [Repeater-Builder] Motorola Spectra Power Cord Reversal
Start with the reverse polarity diode (big and easy to spot where the power leads attach to the chassis) and hope that you get lucky. Milt N3LTQ - Original Message - From: WR9A shortw...@verizon.net To: Repeater-Builder@yahoogroups.com Sent: Saturday, December 12, 2009 7:10 PM Subject: [Repeater-Builder] Motorola Spectra Power Cord Reversal Okay, so I'm a klutz. I wired up the power connector in reverse with no fuse in the line. Needless to say, the radio won't even power on now. Anyone have any idea just how extensive the damage might be? Possible for a Motorola-neophyte to repair himself? I have only basic component-level troubleshooting skills and no service manual. Any advice appreciated. ___ Stephen, WR9A - Lafayette, Indiana Email: wr9a (AT) verizon -DOT- net ___ Yahoo! Groups Links
Re: [Repeater-Builder] Would anyone be interested in.....
Albert, It would be helpfull if you would indicate where you are located since you are not interested in shipping. Milt N3LTQ - Original Message - From: hitekgearhead hitekgearh...@hotmail.com To: Repeater-Builder@yahoogroups.com Sent: Tuesday, December 01, 2009 11:18 AM Subject: [Repeater-Builder] Would anyone be interested in. a couple of Motorola 6 bank chargers for the older MX series HT's. The model number is NTN4831A. I have not checked for functionality but they are in really good shape. For the price, who cares. Just come get them. They are in my way. I would rather not ship, but we can discuss that if you really want them. If no one wants them they are going to the transfer station. Thanks, Albert Yahoo! Groups Links
Re: [Repeater-Builder] Mtr-2000 for 2m use.
Norm, Assuming that your radio is VHF (what were the existing operating frequencies?); the VHF radio comes in two bandsplits in the high power VHF station. There is no way to change one bandsplit to the other. I was involved with a project where incorrect frequencies were entered by someone doing an order resulting in a range 1 receiver and a range two transmitter. The radio ended up being sent back to the factory and replaced by an entirely new unit to correct the problem. The best way to proceed at this point is to have someone with the proper RSS read the radio and give you a printout of the existing codeplug. Milt N3LTQ - Original Message - From: NORM KNAPP nkn...@twowayradio.net To: Repeater-Builder@yahoogroups.com Sent: Monday, November 16, 2009 12:08 PM Subject: [Repeater-Builder] Mtr-2000 for 2m use. I recently obtained a Motorola MTR-2000. It took a lightening hit to the tone remote board, but the repeat functions fine. Upon close inspection, it appears this unit was originally used as a base station before it was a repeater by evidence of ant rel installed. Also it does not have a preselector on the rear. My question is, will this thing work on 2m and will I have to come up with a motorola preselector to use with a 600khz split? S/N 474CZT03xx F.O.: 0960-5003-40067 model no: T5766A type no: FO306B. Thanks es 73 Norm Yahoo! Groups Links
Re: [Repeater-Builder] Re: what pac-rt means
Nice, and easier than the app where the PAC or VRS was wired to the PARK switch on the vehicle transmission. Milt N3LTQ - Original Message - From: wd8chl wd8...@gmail.com To: Repeater-Builder@yahoogroups.comoff-topic into how it works and how it's used. OH Turnpike solved the 'radio not in the charger' problem by wiring the switch to the dome light switch, I think through some sort of flip-flop. When the officer stepped out of the vehicle, it went into repeat. Close the door. Get back in vehicle again, it goes out of repeat. I think there was more to it, too. I know there was also a manual switch on the console... Yahoo! Groups Links
Re: [Repeater-Builder] Re: GE Lookout Repeater related info needed.
In the second picture in the folder there is a 3 position switch to the left of the volume control. The center position is marked RPTR and another position seems to be marked MON. The remaining position marking cannot be read. What is the marking? The term Lookout Repeater is unusual; I recall seeing a Motorola radio manual marked as being a lookout repeater. The unit was, IIRC, comprised of modules from the Business Dispatcher. I believe that the functionality of the unit is unique to a specific type of operation. The use of low power modules suggests that these units were part of a larger system and possibly were used as some form of range extenders. Now the bad news; the PE series modules used in this radio are not the easiest to work on. It has been a long time since I dealt with any of the PE/PY radios but IIRC the frequency sensitive componets were not always on the circuit board. Moving one of these units from 166 to 146 will involve a large amount of work. As always if one wishes to start on such an adventure, manuals are a must along with a knowledge of if and how the unit functions on the existing frequencies. Milt N3LTQ - Original Message - From: lsasmazel lsasma...@comcast.net To: Repeater-Builder@yahoogroups.com Sent: Saturday, October 17, 2009 8:19 PM Subject: [Repeater-Builder] Re: GE Lookout Repeater related info needed. This unit come from Alaska regarding to seller it sat in the boxes and wait to get deployed. But it never happened. Frequencies are ; TX : 166.850 Mhz, , 166.850 Mhz RX: 164.425 Mhz, 164.425 Mhz I just figured out that this is one frequency unit :) Levent - WW2L --- In Repeater-Builder@yahoogroups.com, Eric Lemmon wb6...@... wrote: Levent, The pictures do lend credence to the special part theory. Please advise what the two receive and two transmit frequencies are. Do you have any idea what company or agency owned this device? It's a long shot, but it is always (well, sometimes) possible to track down the previous owner, locate the radio shop that maintained it, and possibly identify the documents you need- if they won't just hand them over. Knowing the frequencies used is a giant first step in that process. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of lsasmazel Sent: Saturday, October 17, 2009 4:49 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: GE Lookout Repeater related info needed. Sorry I forget the mention I put the picture under GE Lookup Repeater folder. There ais one more Number I find it is on the back of the unit and it is PL19D424600G4 this is on the back of the box. 73 Levent - WW2L --- In Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com , Eric Lemmon wb6fly@ wrote: Levent, The component number 19C320943G1 is a SPCL COMP BD. I think it's time to take some pictures of this device, since it seems to be an oddball unit that was not a regular production item. Is there no label or tag on the outside of the box, which might give this thing a name or a model number? Without a clear identification of the whole unit, all we can determine is that it is a special part that incorporates some PE handheld modules. Regarding power requirements, a typical 5-watt radio draws about 2 amperes during transmit. Add 1 amp or so for running the controller, and you can assume that a 5-amp supply will suffice. But, be careful to determine what voltage is required to run this thing, before hooking up your favorite Astron power supply. The unit may require 7.5 or 10 VDC, and you don't know that without more documentation. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com [mailto:Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com ] On Behalf Of lsasmazel Sent: Saturday, October 17, 2009 4:06 PM To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Subject: [Repeater-Builder] Re: GE Lookout Repeater related info needed. Eric, Thanks for all info. Very interesting data you have I was trying to understand with visual inspection. Even box has 4 position for the frequency selection it has only 2 xtal unit on the receiver and 2 xtal unit on the TX board. I was thinking that it was switching xtals between TX and RX board. Can you tell me what are the power supply requirements for these units. Also at the back there are 3 RF connectors (SO 239) one is marked as RX antenna other is just ANT and the third one which is on the TX board says RX RF IN ? I don't have any clue on that. I was thinking to replace OSC xtals with ham band ones and also modify or change the RX filter section. May be I am too much
Re: [Repeater-Builder] Emergency Medical Systems Duplex / Repeater UHF Mobile Radio Model Q2203A
Joe, I assume that you have what looks like a standard Micor mobile that grew a big extension on the back end to house the duplexer and some other bits. Some of these units also added an external housing for a secondary receiver and control electronics on what were termed the Med sub channels (4 freqs in the 458 range). Your basic radio is a full duplex 12 channel, 450-470 range, RX above TX, with TX power of 50 watts reduced to 30 watts out of the duplexer. Some of the parts of the system however are missing as part of the control/repeat system was in the control head. The duplexer is a 5 MHz split, notch type and may be asymmetrical (more notches on one side than the other), that was tuned to cover the 463.000 to 463.175 and 468.000 to 468.175 range. The basic radio was still built around the mobile UHF Micor concept of a single channel element providing both the RX and TX signals. Conversion possibilities exist for the basic radio modules. Milt N3LTQ - Original Message - From: Joe k1ike_m...@snet.net To: Repeater-Builder@yahoogroups.com Sent: Saturday, October 17, 2009 6:49 PM Subject: [Repeater-Builder] Emergency Medical Systems Duplex / Repeater UHF Mobile Radio Model Q2203A Sorry about the first message with the wrong Subject line. I was cut/and/pasting and hit the send key. Here is the corrected message... I just found an orphan EMS model Q2033A mobile at my door. No cables or head, just the transceiver and receiver boxes. These were used on the local ambulance and were full duplex, plus repeater function. Is there any use for these on the ham bands? The duplexer looks to be too wide banded for ham use, I remember playing with one of these duplexer's years ago. Looks like I just have Micor spare parts? 73, Joe, K1ike Yahoo! Groups Links
Re: [Repeater-Builder] Narrow(er) band FM
Tony, The GP/GM series radios were built for either 25K operation or 12.5K operation. They did not support both bandwidth spacings. Milt N3LTQ - Original Message - From: Tony KT9AC kt...@ameritech.net To: Repeater-Builder@yahoogroups.com Sent: Sunday, October 04, 2009 7:49 PM Subject: Re: [Repeater-Builder] Narrow(er) band FM I have a GM300 narrowband mobile (M34GMC00D3A), how do I know when its programmed to do 12.5Khz? There is nothing in RSS to select, where the MTS2000 CPS allows unique modes for narrowband. Thanks, Tony Cort Buffington wrote: I said I'd report back XYL and I were out with the EX500s today. I copied the channel we normally use for simplex and changed nothing but made it a narrower channel. Results. Noise squelch seems sloppier (normally I use DPL or PL, so that really isn't to big of a deal), audio fidelity is reduced. We weren't far enough apart to really test range. I think the audio quality was still pretty good, but when do do ok, go back to channel 3 now... It's quite clear the narrow sounds quite noticeably better than the narrower. 73 DE N0MJS P.S. I also wonder about the frequency accuracy of radios going to the super-narrow band. I've looked at a lot of ham rigs on my service monitor. They are usually worse than the commercial radios in this area. Isn't that going to have a more pronounced effect? On Oct 3, 2009, at 4:22 PM, John Sehring wrote: I think it's worth repeating (no pun intended!): 0. In a narrower band FM system, with only the carrier present, you may well get a bit more ultimate quieting sensitivity (but not necessarily better SINAD) as the receiver's IF bandpass (selectivity) is narrower, letting less noise thru. However, the question is: how much of that slightly increased sensivity is actually useable? 1. Reducing FM deviation to less than about 5 kHz results in less power in the sidebands, which sidebands convey the intelligence (the carrier is just there to enable the usual demodulation (detection) process). As the detector needs the sideband energy, even granting (1) above, you'll have less recovered audio available. The signal's spectrum then begins to resemble that of an equivalently-modulated AM signal; the major difference is that with an FM signal, the carrier is 90 degrees out of phase with the sidebands, whereas with AM, carrier and sidebands are in phase. 2. Reducing FM deviation (and narrowing IF bandpass) allows more distortion in receivers at low (fringe) signal levels, so it's less able to deal with things like multipath propagation, AM noise, FM noise (yes, there is such a thing), and co-channel interference. Signal to noise ratio is thus reduced. 3. Squelch action becomes sloppier because the demodulated audio spectrum which is used for noise-operated squelch is quite a bit less when using narrower band FM. Rule of thumb for the squelch detector's bandpass: it extends from A) just above the voice audio band, say, 4 kHz, to B) about one-half the IF bandwidth. The latter is distinctly less, so the squelch sensing bandpass is less making squelch action less responsive. If you use an audio spectrum analyzer to look at a demodulated FM signal, you can see the spectral differences between 75 (FM broadcast), 25 (NTSC TV sound), 15, 5, and 2.5 kHz deviated signals, esp. as the signal strengths are reduced to zero. --John Yahoo! Groups Links
Re: [Repeater-Builder] Diplex antenna installation using coaxial cable for 10M and 6 M
Steve, The document in question is on the repeater-builder WEB site, not the files area for this group. There were two documents produced by Motorola , each dealing with specific antenna combinations allowing the use of 2 antennas to cover areas of VHF lowband. One dealt with using two Motorola series fed base loaded antennas to cover two 400 KHz segments of low band seperated by at least 4 MHz. The other dealt with adding a series fed base loaded antenna to an installation that used a ball mount quarter-wave whip. There was also a ball mount quarter-wave whip with a matching section in the coax feed which allowed for extra wide bandwidth operation. Motorola had one and Antenna Specialists had a similar version. The standard base loaded antenna usually covers no more than a 1 MHz segment of lowband before the SWR goes above 2:1. I have often seen cases where the programming of radios well exceeded the abilities of the antenna system, however one has to remember that if the usage was localized, such as on a fire scene, the only thing that mattered was if you could be heard by everyone in the immediate area, often no more than a half a mile. I ran into a situation where county A's dispatch was a 46 MHz frequency and the adjoining country used 33 MHz channels. In this situation the usage for units from county A when in county B was only mutual aid on the scene operations. Thus the radios from county A were programmed for county B's operations channels but the antenna was left as a 46 MHz base loaded whip. The reflected power was almost equal to the foward power on county B's ops channels but from the perspective of the users things worked fine. Diplex packages were eventually installed as the vehicles were changed out, but it took quite a long time to get past the initial setup. The standard package diplex kit for two Motorola Spectrum base loaded antennas consists of a PL-259 T-connector, a UHF barrell, 4 PL-259s with reducers, and a length of coax. Two Spectrum base loads are required as well. The critical length of coax is from the NMO mount to the T-connector. The length of coax from the output of the T-connector to the radio was not critical. When the antennas are properly mounted and tuned for the individual segments of low band, the combination usually does not add any more than 1-2 watts in reflected power within the resonant segments. The chart in the document was developed specifically for the Spectrum series series fed LB antenna. THE MEASUREMENTS IN THE CHART WILL NOT WORK WITH SHUNT FED COILS! I have used many of these packages on fire/ems and police vehicles and they work very well. The Spectrum antennas can get rather picky about the ground plane. As long as the individual antennas are able to be tuned to resonance the combination works. And the standard operating ranges of the Spectrum series antenna are 29.7-36 MHz, 36-42 MHz, 42-50 MHz, and 66-88MHz, there are no other coil ranges . Milt N3LTQ - Original Message - From: steven_schultz92 steven.schult...@gmail.com To: Repeater-Builder@yahoogroups.com Sent: Friday, September 11, 2009 1:42 PM Subject: [Repeater-Builder] Diplex antenna installation using coaxial cable for 10M and 6 M Hello, I am new to this group. A fellow ham recommended I look into this group to answer a question I have. I am also interested in amateur radio equipment design and building so this motivated me to join the group as well. My question is related to the design of a diplex low band antenna installation. It is described in a Motorola technical publication 68P80100W86-A dated 9/27/85. This note describes how to connect two low band antennas (30 to 50 MHz) to a common coax. A coaxial cable cutting chart is provided in the note. The installation is such that a given length of coax is connected between say a 30 MHz antenna and a T connection and another different given length of coax is connected between say a 50 MHz antenna the T connection. The third connection of the T connection is connected to the radio with an arbitrary length of coax. The cutting chart refers to what they call standard RG-58A/U coax. For a 30MHz and 50MHz antenna installation the chart prescribes a 47 inch length of coax for feeding the 30 MHz antenna and a 100 inch length of coax for feeding the 50 MHz antenna. My ham friend says these are 1/4 wavelengths of transmission line for the opposite band (100 inch is approx 1/4 at 30 MHz and 47 inch is approx 1/4 at 50 MHz). Being an analytical guy I modeled the antenna system in both Ansoft Designer and an antenna modeling program. In Ansoft Designer the antennas were modeled as a series RLC load with 50 ohms at resonance and a Q of 15. Transmission lines were modeled with VF equal to that of RG-58A/U coax. In the antenna modeling program the antennas were modeled as 1/4 verticals with transmission lines having VF=0
Re: [Repeater-Builder] Re: Antenna SWR = Desense?
While you are out at the antenna, stick the wattmeter in line and check the foward/reflected there with the antenna and the dummy load. My guess is that you will quickly find your problem. I would check the connection to the DB-224 coax as well as the connections to each element. Also check the center connection. 30 foward and 3 reflected is a whole lot higher than I would accept; at least 10% of your RF out is being reflected. Milt N3LTQ - Original Message - From: tahrens301 tahr...@swtexas.net To: Repeater-Builder@yahoogroups.com Sent: Tuesday, September 01, 2009 4:02 PM Subject: [Repeater-Builder] Re: Antenna SWR = Desense? Hi Joe, The repeater/duplexer is in my workshop (a large metal building). The heliax goes out the window to a smaller portable building about 100' away (horizontally spaced). The antenna is on that building about 10' off the ground. Don - took the dummyload analyzer to the end of the hard line, fed it into the iso-tee there. No desense is noted. Something's not right when the antenna gets hooked up. Maybe I should put up the ringo for a test. at least it's probably a bit better of a match. --- In Repeater-Builder@yahoogroups.com, Joe k1ike_m...@... wrote: You state DB-224 100' horizontally 10' vertically separated. I don't understand what you mean by that. Joe tahrens301 wrote: However, putting the system on the antenna (a 150-160 mhz DB-224 100' horizontally 10' vertically separated) through a metal building fed with 7/8 heliax, there seems to be no end to the desense! Yahoo! Groups Links No virus found in this incoming message. Checked by AVG - www.avg.com Version: 8.5.392 / Virus Database: 270.13.73/2338 - Release Date: 08/31/09 17:52:00
Re: [Repeater-Builder] Need to pay someone to properly install repeater system in our school
A good starting point would be to state the city in which you are located. - Original Message - From: rddow...@swbell.net To: Repeater-Builder@yahoogroups.com Sent: Thursday, July 23, 2009 2:09 PM Subject: [Repeater-Builder] Need to pay someone to properly install repeater system in our school We converted an old Kroger grocery store into a charter school. The building has metal roofing and lots of steel beams, making it very difficult to get a good signal on our Nextel and AtT cell phones. So far we have installed antennas and amplifiers, to no avail. We would like to pay someone to visit the school and make everything work. Any suggestions. R. Dale Dowell, CFO Focus Learning Academy Yahoo! Groups Links No virus found in this incoming message. Checked by AVG - www.avg.com Version: 8.5.392 / Virus Database: 270.13.23/2254 - Release Date: 07/22/09 05:59:00
Re: [Repeater-Builder] Re: Building HT antennas
The tuning of the Centurion antenna is very simple, tune the trimmer cap for maximum transmitted signal. Use anything that gives an indication; service monitor, field strength meter, whatever. You will only cover at most 1 MHz with ANY antenna on low band other than a couple of specially designed broadband split-ball mount mobile whip designs. Since you say the primary usage will be fixed, use the antenna adaptor attachment that screws onto the universal connector and get a 50 ohm connection to whatever fixed antenna you want. Use the Centurion antenna for portable operation. If you absolutly have to waste time screwing around with different antennas then remove the existing antenna connector and rework the design of the portable to use a coaxial antenna connector. Milt N3LTQ - Original Message - From: Albert hitekgearh...@hotmail.com To: Repeater-Builder@yahoogroups.com Sent: Sunday, July 12, 2009 2:25 AM Subject: [Repeater-Builder] Re: Building HT antennas Let me first say thanks to everyone for all of their input and information. I am familiar with the NAB6064A/B heliflex antenna but do not actually have one of those. I do actually own one of the Centurion/Antennex model EXL antennas that Milt mentioned. The only down side is I do not have the tuning information. Maybe if I called them I could acquire that information. I do plan on only using the radio for the 6m amateur band, so I would roughly only be covering three to four MHz. I was hoping to get away with a single antenna for that purpose. Maybe I could incorporate a small telescopic section into my design to compensate for the width of the band. Also, this project is designed to use in a mostly stationary situation, and I was thinking of incorporating a spring or something similar at the base of the antenna to minimize the shock to the antenna connector. It might be best to take this a different direction though, and just utilize the public safety mic with it's antenna connector. That way I could easily attach an expedient antenna for increased range in the field while stationary, and then replace it with a duck type antenna while on the move. ((Yes, I know Motorola never made a low band rubber duck antenna for the PSM. That would be another undertaking) So thanks again for the input. I will let you know what I come up with. Albert KI4ORI Yahoo! Groups Links No virus found in this incoming message. Checked by AVG - www.avg.com Version: 8.5.375 / Virus Database: 270.13.11/2232 - Release Date: 07/11/09 17:56:00
Re: [Repeater-Builder] Building HT antennas
Albert, The Achillies heel of all low band portables is the lack of adaquet ground plane. At UHF the frame and circuit ground plane surfaces are satisfactory to provide the ground plane for the quarterwave radiator to work against. At VHF the ground plane surface area is reduced but is still of sufficient size to allow for reasonable performance. At low band however the ground plane surface area is a very small fraction of the wavelength resulting in miserable performance regardless of the antenna installed. Remember that at low band a quarterwave can vary in length from approximatly 8 ft in the 30 MHz range to slightly less than 5 ft at 50 MHz. Stick with the regular antenna cut for frequency. At one time there was an aftermarket antenna made by Centurion that used a base load coil and a tuning capacitor to resonate the antenna (tuned for max signal strength on Tx). These seemed to work OK for a single or narrow frequency range. Centurion was purchased by Laird (IIRC) and the availability of these antennas seems to have dried up. I tried to get some with a different connector several years ago and got brushed off. My favorite low band performer was the MH-10 followed by the MT500. Both easily outperform the MT1000 any day but have the limitation of crystal control and limited frequency capacity, and now lack of parts availability. The entire Genisis line suffers from a design flaw regarding the connection of the antenna to the main circuit board. The bottom of the connector bends 90 degrees to solder to the circuit board. This joint or the bend itself will break due to the stresses placed on the antenna connector by the antenna. The bigger the antenna the quicker this joint will fail. The failure is easily seen by checking the solder connection at the top of the main circuit board. Sometimes it is necessary to use a magnifying lens to see the cracked solder joint but usually it will pe plainly visible. Resoldering the joint can fix many no transmit or poor receive complaints. Milt N3LTQ - Original Message - From: Albert hitekgearh...@hotmail.com To: Repeater-Builder@yahoogroups.com Sent: Friday, July 10, 2009 3:55 PM Subject: [Repeater-Builder] Building HT antennas Hey guys, I posted this question over on the HT600e forum but didn't get anything. I was wondering if anyone here could be of assistance. I recently acquired a low band MT1000 for use on the 6m band. It has a nice new commercial antenna but I was wanting to do something a little better. No one that I can find supplies or can supply me with a better antenna for this radio. Even smiley antenna, my usual go to company for custom antennas for the Genesis line can't help me. So I was thinking of building my own. My first thought, since the antenna connector on the MT1000 is basically a 1/4-32 hole, I could thread a piece of aluminum round stock to create a base. Then I could just make a 1/4 wave whip from stainless rod. I know it would be silly long but it is a start. If I do this, do you think I should just use the standard 1/4 wave vertical formula? Would I need to compensate for the HT's lack of a ground plane? Any thoughts would be appreciated. Thanks Albert KI4ORI Yahoo! Groups Links No virus found in this incoming message. Checked by AVG - www.avg.com Version: 8.5.375 / Virus Database: 270.13.10/2231 - Release Date: 07/11/09 05:57:00
Re: [Repeater-Builder] ARR UHF GaAsFET - free, not working
Jeff, If you still have the Micor stuff I will be glad to take it off your hands. Send me a direct e-mail and we can work out the finer details. Milt N3LTQ - Original Message - From: 'Jeff DePolo' j...@broadsci.com To: Repeater-Builder@yahoogroups.com Sent: Sunday, June 28, 2009 1:33 PM Subject: [Repeater-Builder] ARR UHF GaAsFET - free, not working I pulled out an ARR P432VDG GaAsFET preamp today, it's no longer working. Anyone want it? I've standardized on Angle Linear; this ARR is one of the few I still have in service and I have no interest in getting it repaired.. If you want it, call ARR and get an RMA number for the repair on Monday and I'll ship it to them to repair, and then they can ship it back to you to save on shipping costs. First reply gets it. Please reply *to the list* so everyone else sees that it's spoken for. Also, if anyone wants any, I have boxes full of mobile Micor UHF parts that I'm going to chuck. Mostly exciters (regular and wide-spaced), audio/squelch boards, PL boards, cover shields, etc. No receivers or PL reeds. U pay shipping. --- Jeff WN3A Yahoo! Groups Links No virus found in this incoming message. Checked by AVG - www.avg.com Version: 8.5.375 / Virus Database: 270.12.94/2207 - Release Date: 06/28/09 17:54:00
Re: [Repeater-Builder] Re: Help Identifying Matrix in Mastr II
That unit would have needed a C800 or C900 control head and was most likely a SP build for a Federal agency, several generations back as radio systems go. The dual RX allowed the radio top have good sensitivity in both the 163 and 167 ranges as the front end filtering were not that wide and/or allowed for dual receive. The 1st IF outputs were combined and passed to a comman detector. A switching matrix would have selected the appropriate ICOMs for TX and RX based on the channel selector position. A PSLM board might have been installed to allow scanning on one receiver. Basically a you tell us what you need and we will build it project. Hope you have a manual or lots of patience to sort things out. Milt N3LTQ - Original Message - From: Laryn Lohman lar...@hotmail.com To: Repeater-Builder@yahoogroups.com Sent: Tuesday, May 26, 2009 10:12 PM Subject: [Repeater-Builder] Re: Help Identifying Matrix in Mastr II the part number 19B233115G1 appears to be a box rather than a component. Yes, as stated, it is the box containing the matrix. Please advise the frequencies of the ICOMs, along with their positions in the radio. TX-- F1 167.2625 F2 .3125 F3 .400 F4 .5625 F5 .750 F6 .5375 F7 .650 F8 .3625 RX1-- F1 163.925 F2 .8875 F3 .8625 RX2-- F1 167.2625 F2 .3125 F3 .400 F4 .5625 F5 .750 F6 .650 F7 .3625 RX2 has only an RF section and oscillator section. The IF area is not populated except for 4 or 5 components. I suspect that you have an IMTS or MTS mobile telephone drawer, but the frequencies will provide valuable information. Naw I don't think so. And the radio is not duplexed... Hope this helps. Laryn K8TVZ 73, Eric Lemmon WB6FLY Yahoo! Groups Links
Re: [Repeater-Builder] Rule Question
Bill, Obviously the place to start is the appropriate section of the Rules which apply to the service where you are licensed . That said, I believe that different sections treat control stations meeting the 6.1 meter rule differently. You are correct to assume that the shovel is being used to deposit Shineola on your boots. Milt N3LTQ - Original Message - From: Bill Powell w...@att.net To: Repeater-Builder@yahoogroups.com Sent: Wednesday, April 29, 2009 7:30 PM Subject: [Repeater-Builder] Rule Question I know it's off-topic but I needed a starting place. Please refer me to someplace appropriate instead of flames. I'm looking for clarification on 6.2m control stations. I'm being told (by a dealer) that, in the eyes of the FCC, they are treated the same as a mobile and do not need to be included in the license. I think I'm being shoveled a fresh load... Tkx, Bill - WB1GOT Yahoo! Groups Links
Re: [Repeater-Builder] QUANTAR RPT.
IIRC the Quantar radio was developed later than 1991, but the grey cells have been known to get confused. The Quantar radio can be programmed to do many things with the proper hardware. A stock Quantar does not respond to any commands other than wireline tone remote sequences. Over the air control by DTMF or other signalling requires additional hardware. Milt N3LTQ - Original Message - From: w7...@comcast.net To: Repeater-Builder@yahoogroups.com Sent: Saturday, April 25, 2009 3:38 PM Subject: [Repeater-Builder] QUANTAR RPT. Hello Group, Getting ready to take my Quantar VHF rpt. to Motorola shop Monday to be programmed. I have a few questions, so I do not sound so ignorant to the tech doing the programming. In RSS, is there a setting that will send an alert if the AC power to rpt. was interrupted and restored. (Perhaps a CW phrase?). Is the machine capable of DTMF commands for Transmitter Knockdown? Can the squelch be Loosened or Tightened via DTMF control? (I am going to use encode/decode PL, but would be a nice feature!) The rpt. will be programmed single channel 25 kc split, conventional analog NOW, and in 2013, be reprogrammed to 12.5 kc Narrow Band. Is it possible to program a second channel for narrow band, (same fx as wide band), and using DTMF control to switch channels, so I do not have to take rpt. back to shop and shell out $100 or so ! This 1991 rpt. is all new to memy other one is an MSR 2000 (Has not let me down is 16 years!) Tim Hardy W7TRH / AFA0TP Vashon Is. Wa.
Re: [Repeater-Builder] (OT) APCO P25 horror stories anyone?
Chuck, your experience parallels what many users in Pennsylvania have experienced. The only difference here is that the state continues to throw money at a dead animal believing that it can be made to stand. The general opinion here is that in very strong signal conditions (like in the lab) the system sounds OK. In weak signal locations and the real world the system can easily fall apart. Of course we are referring to the Ma/Com Open Sky system which is a proprietary digital system and is NOT P25. MIlt N3LTQ - Original Message - From: Chuck Kelsey wb2...@roadrunner.com To: Repeater-Builder@yahoogroups.com Sent: Tuesday, April 07, 2009 1:02 PM Subject: Re: [Repeater-Builder] (OT) APCO P25 horror stories anyone? Have you read the engineering reports? I used one of the radios and wasn't very impressed (actually I was quite disappointed). And I was a cheerleader for the system up until then. Chuck And M/A-Com is suing the state because they DID meet the original specs/requirements, and the state is just trying to back out of spending the money. Crooked gov't? naaahhh... Yahoo! Groups Links
Re: [Repeater-Builder] CDM500 powerup issues
Brian, The CDR package requires the use of an additional connection to tell the CDM mobiles to turn on at power up. Right now if you press and release the center button of the voulme control the radio should turn on. Do this to each radio. The radios will remain on until power is disconnected. In order to automate the procedure, obtain another 16 pin plug and the female pin connector with wire attached. Insert wire into pin 10 of the 16 pin connector. Connect the other end through a 3A fuse to the fan power lead. Now when you plug in the unit the radios will power on. Good Luck Milt N3LTQ - Original Message - From: Brian Raker brian.ra...@gmail.com To: repeater-builder repeater-builder@yahoogroups.com Sent: Sunday, April 05, 2009 7:45 PM Subject: [Repeater-Builder] CDM500 powerup issues Hi All, I've recently acquired a CDR500 repeater and I'm in the process of checking it out and making sure that everything works as best as I can tell before reprogramming and repurposing it. However, I seem to have run into a snag. The unit has two CDM750 403-470 4-channel radios, a 6-well duplexer and a 4 well filter (I think, not relevant at the moment), and a RICK (HLNB). When I power on the unit, the intake fan on the bottom fires up, but nothing else seems to happen. No lights appear on the radio faces, and the RICK doesn't do anything likewise. I've traced the interface cables and they are plugged in right, the power cables are good to the radios, and the radios are known good (used a tabletop supply from a GM300 and 16-pin plug from the same GM300). I unfortunately don't have or know of anything to test the RICK out with. Does anyone have any suggestions on how to further test this unit out? Thanks! -Brian / KF4ZWZ Yahoo! Groups Links
Re: [Repeater-Builder] CDM500 powerup issues
Oops, forgot to say the additional 16 pin plug goes into the center (ACC) jack on the RICK module. - Original Message - From: Milt men...@pa.net To: Repeater-Builder@yahoogroups.com Sent: Sunday, April 05, 2009 9:21 PM Subject: Re: [Repeater-Builder] CDM500 powerup issues Brian, The CDR package requires the use of an additional connection to tell the CDM mobiles to turn on at power up. Right now if you press and release the center button of the voulme control the radio should turn on. Do this to each radio. The radios will remain on until power is disconnected. In order to automate the procedure, obtain another 16 pin plug and the female pin connector with wire attached. Insert wire into pin 10 of the 16 pin connector. Connect the other end through a 3A fuse to the fan power lead. Now when you plug in the unit the radios will power on. Good Luck Milt N3LTQ - Original Message - From: Brian Raker brian.ra...@gmail.com To: repeater-builder repeater-builder@yahoogroups.com Sent: Sunday, April 05, 2009 7:45 PM Subject: [Repeater-Builder] CDM500 powerup issues Hi All, I've recently acquired a CDR500 repeater and I'm in the process of checking it out and making sure that everything works as best as I can tell before reprogramming and repurposing it. However, I seem to have run into a snag. The unit has two CDM750 403-470 4-channel radios, a 6-well duplexer and a 4 well filter (I think, not relevant at the moment), and a RICK (HLNB). When I power on the unit, the intake fan on the bottom fires up, but nothing else seems to happen. No lights appear on the radio faces, and the RICK doesn't do anything likewise. I've traced the interface cables and they are plugged in right, the power cables are good to the radios, and the radios are known good (used a tabletop supply from a GM300 and 16-pin plug from the same GM300). I unfortunately don't have or know of anything to test the RICK out with. Does anyone have any suggestions on how to further test this unit out? Thanks! -Brian / KF4ZWZ Yahoo! Groups Links Yahoo! Groups Links
Re: [Repeater-Builder] Fw: [DSTAR_DIGITAL] FCC Ruling on Repeater Definition
Simplex repeater being somewhat of an oxymoron, I believe the proper definition would be a store and foward system since the message of whatever nature (digital or analog) is stored and then fowarded (retransmitted). It's easier to call it a simplex repeater to convey the end result of the operation. Milt - Original Message - From: Dave Gomberg da...@wcf.com To: Repeater-Builder@yahoogroups.com Sent: Wednesday, March 25, 2009 12:33 AM Subject: Re: [Repeater-Builder] Fw: [DSTAR_DIGITAL] FCC Ruling on Repeater Definition At 16:34 3/24/2009, Jeff Condit wrote: What do you call it when messages are recorded and then retransmission begins right after reception ends? By this definition it would not constitute a simplex repeater, right? That is exactly m y understanding of what simplex repeater means Jeff Condit -- Dave Gomberg, San Francisco NE5EE gomberg1 at wcf dot com All addresses, phones, etc. at http://www.wcf.com/ham/info.html - Yahoo! Groups Links No virus found in this incoming message. Checked by AVG - www.avg.com Version: 8.5.278 / Virus Database: 270.11.25/2019 - Release Date: 03/23/09 18:51:00
Re: [Repeater-Builder] Maratrac CTCSS injection point
Since the Maratrac radio is basically a Maxtrac with a larger PA, I would take a look at the 16 pin accessory connector on the exciter/receiver portion of the Maratrac radio and compare it to a Maxtrac. Without specific documentation I'm going from memory but there is a Maxtrac configuration that operates as a community repeater. HOWEVER, if there is no need for multiple tone codes, use the radio to generate the tones rather than trying to mess around with controller based tones. Milt N3LTQ - Original Message - From: jstechnicalservice jska...@in-touch.net To: Repeater-Builder@yahoogroups.com Sent: Friday, March 20, 2009 9:53 PM Subject: [Repeater-Builder] Maratrac CTCSS injection point Can someone tell me where I would need to inject the subtone from a tone panel to the modulator of a maratrac. I'm attempting to build a backup repeater for our dept and have all the connections figured out except that one. I'm not planning to use a control head just the radio itself for transmit only. Thanks. Jeff Skaggs Concord-Greene FD Yahoo! Groups Links No virus found in this incoming message. Checked by AVG - www.avg.com Version: 8.5.278 / Virus Database: 270.11.21/2014 - Release Date: 03/20/09 06:59:00
Re: [Repeater-Builder] Mobile Repeater
Go with the MTR2000. Let's assume that the MTR is a 100 watt radio. I have been runing a MTR at 50% power for the last several years. No problems at all. WIth the duplexer loss and running at half power, you will have less than 50 watts which will work fine in your command post setting. Set it and forget it. Polite legal ID included with the internal controller. The handhelds are HT1250 they could have the non-standard reverse burst function set to eliminate the squelch crash that would occur with the Kenwood, but the Spectra's would not have that capability. Milt N3LTQ - Original Message - From: rahwayflynn mafl...@att.net To: Repeater-Builder@yahoogroups.com Sent: Saturday, March 21, 2009 11:18 AM Subject: [Repeater-Builder] Mobile Repeater I was asked by a Technical Rescue group to help them set up a repeater for a mobile command post they are building. The chassis is MCI bus, so it's not going off road. Here's the notes: * The are licensed in commercial UHF. * The bus has both 12V and 24V available from 2 different battery sets * The have access to a commercial style rack with shock mounts * Their hand-held radios are all HT1250, multiple varients. Some of the members have opted to install Motorola Spectra radios in their POV. * The have access to an MTR2000 station and a Kenwood TKR850 from a local car dealership. The can pick either, the other goes to another non-profit. * The antenna is an looks like an RFS BA1012 on a 20' push up pole (they are attempting to obtain a 60' Wilburt mast from a television station) I'm leaning toward the MTR2000 as has better specs and it a high power unit (will not require an external PA). Is there something I am missing in pointing them at the MTR station? Martin Yahoo! Groups Links No virus found in this incoming message. Checked by AVG - www.avg.com Version: 8.5.278 / Virus Database: 270.11.22/2015 - Release Date: 03/20/09 19:01:00
Re: [Repeater-Builder] Micor Card needed - TLN1251A
I suppose that it could be used for that also, I have previously only seen it used in base applications but the card is a 2 state device and could control many things. - Original Message - From: Gary Glaenzer To: Repeater-Builder@yahoogroups.com Sent: Saturday, March 14, 2009 8:03 AM Subject: Re: [Repeater-Builder] Micor Card needed - TLN1251A Milt; I believe it was to change operation from PL operation to CS operation, not just receive, but 'repeat' also IOW, change it to a carrier-in operated repeater Gary - Original Message - From: Milt To: Repeater-Builder@yahoogroups.com Sent: Friday, March 13, 2009 11:16 PM Subject: Re: [Repeater-Builder] Micor Card needed - TLN1251A The typical application is to be able to drop RX PL from the console. Not just to check for co-channel users (ie the monitor function which is reset by PTT) but to go to and stay in carrier squelch even when transmitting until commanded back to PL receive. Hypothetical example: The medivac helicoptor (or your neighboring mutual aid department) does currently have the proper PL for your county. Dropping PL receive lets you hear him transmit and you can reply to him. When the incident is over the PL receive is reenabled. Milt N3LTQ - Original Message - From: Scott Zimmerman n3...@repeater-builder.com To: Repeater-Builder@yahoogroups.com Sent: Friday, March 13, 2009 11:00 PM Subject: Re: [Repeater-Builder] Micor Card needed - TLN1251A Eric, I'm not sure. I found (1) in my stash that I have collected at hamfests and whatnot over the years. I have no idea what model numbers these would have been found in. Knowing Motorola (and my dumb luck) there weren't very many made. Scott Scott Zimmerman Amateur Radio Call N3XCC 474 Barnett Rd Boswell, PA 15531 - Original Message - From: Eric Lemmon wb6...@verizon.net To: Repeater-Builder@yahoogroups.com Sent: Friday, March 13, 2009 9:40 PM Subject: RE: [Repeater-Builder] Micor Card needed - TLN1251A Scott, What type of Micor station would use this card? 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Scott Zimmerman Sent: Friday, March 13, 2009 8:18 AM To: motorola-u...@yahoogroups.com; Repeater Builder List Subject: [Repeater-Builder] Micor Card needed - TLN1251A I am in need of a few TLN1251 cards. These are more commonly known as private line control modules. They have 2 momentary switches in the front labeled Operate PL and Operate Carrier Squelch. They have 2 tone decoders on board - 1550 Hz and 1450 Hz. If you or anyone you know has any they don't need, let me know. Thanks, Scott Scott Zimmerman Amateur Radio Call N3XCC 474 Barnett Rd Boswell, PA 15531 Yahoo! Groups Links Yahoo! Groups Links Checked by AVG - www.avg.com Version: 8.0.237 / Virus Database: 270.11.13/2000 - Release Date: 03/13/09 18:00:00
Re: [Repeater-Builder] Micor Card needed - TLN1251A
The typical application is to be able to drop RX PL from the console. Not just to check for co-channel users (ie the monitor function which is reset by PTT) but to go to and stay in carrier squelch even when transmitting until commanded back to PL receive. Hypothetical example: The medivac helicoptor (or your neighboring mutual aid department) does currently have the proper PL for your county. Dropping PL receive lets you hear him transmit and you can reply to him. When the incident is over the PL receive is reenabled. Milt N3LTQ - Original Message - From: Scott Zimmerman n3...@repeater-builder.com To: Repeater-Builder@yahoogroups.com Sent: Friday, March 13, 2009 11:00 PM Subject: Re: [Repeater-Builder] Micor Card needed - TLN1251A Eric, I'm not sure. I found (1) in my stash that I have collected at hamfests and whatnot over the years. I have no idea what model numbers these would have been found in. Knowing Motorola (and my dumb luck) there weren't very many made. Scott Scott Zimmerman Amateur Radio Call N3XCC 474 Barnett Rd Boswell, PA 15531 - Original Message - From: Eric Lemmon wb6...@verizon.net To: Repeater-Builder@yahoogroups.com Sent: Friday, March 13, 2009 9:40 PM Subject: RE: [Repeater-Builder] Micor Card needed - TLN1251A Scott, What type of Micor station would use this card? 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Scott Zimmerman Sent: Friday, March 13, 2009 8:18 AM To: motorola-u...@yahoogroups.com; Repeater Builder List Subject: [Repeater-Builder] Micor Card needed - TLN1251A I am in need of a few TLN1251 cards. These are more commonly known as private line control modules. They have 2 momentary switches in the front labeled Operate PL and Operate Carrier Squelch. They have 2 tone decoders on board - 1550 Hz and 1450 Hz. If you or anyone you know has any they don't need, let me know. Thanks, Scott Scott Zimmerman Amateur Radio Call N3XCC 474 Barnett Rd Boswell, PA 15531 Yahoo! Groups Links Yahoo! Groups Links
Re: [Repeater-Builder] Understanding Intermod
Quite true Gary. There are a whole lot of situations that can mess up things for everyone, and the poisen pill does not have to be directly on site to be the problem. Milt - Original Message - From: Gary Glaenzer To: Repeater-Builder@yahoogroups.com Sent: Sunday, March 08, 2009 12:10 PM Subject: Re: [Repeater-Builder] Understanding Intermod Milt; Not to make light of your observation just the program spitting out all the combinations that COULD cause a problem But..this discussion brought to mind a statement made by a Motorola engineer at a school about multicouplers, splitters, combiners, etc back in 1984; they were discussing the multitude of repeaters on the John Hancock building (or maybe it was Sears Tower) in Chicago One 'wrong' frequency allowed onto a site can 'poison' the site for everyone I guess that means run the IM program BEFORE any new TX is added...not after problems crop up Gary - Original Message - From: Milt To: Repeater-Builder@yahoogroups.com Sent: Saturday, March 07, 2009 10:31 PM Subject: Re: [Repeater-Builder] Understanding Intermod Kevin, I recall a case where several UHF community repeaters were installed at a single site. This was not a pretty picture since there was no way to achive vertical seperation and transmitter combiners/receiver multicouplers were not as popular as they are today. An intermod study weas run on the site and at either the 5th or 7th order, every receiver on the site should have been experiencing intermod from a combination of all the transmitters. Of course this was not the case. It was just the program spitting out all the possible combinations that COULD cause a problem. All intermod programs just do the mathmatical combinations and report the outcomes, even outragous ones that are not likely to naturally occur. Some do a better job than others of taking into account things like receiver bandwidth and other factors. Actually finding the source where the mix is taking place much more difficult. The benefit of such programs is that they can easily do the math for you, but you have to decide which numbers are good possibilities and which ones are red herrings. Milt N3LTQ - Original Message - From: Kevin King kc6...@comcast.net To: Repeater-Builder@yahoogroups.com Sent: Saturday, March 07, 2009 8:59 PM Subject: RE: [Repeater-Builder] Understanding Intermod Bob Ok so much for the software. One other user today mentioned a possible issue with another repeater. 147.300. All I had been looking at with the software were the transmitters at his site. Ok so I plug that into the mix of xmiters in the software and bingo. A+B-C 146.70 + 146.70 - 147.30 = 146.100. The repeater 146.70 does have a circulator. Again this intermod is not my best area. I had the repeater owner keep the 146.700 xmitter up them had him hit the 147.30 with an HT and yep we got a burp of noise. But he heard at least 3 repeaters come up. So if this mix is the one that is causing all the issues, now we just need to find where the mix is occurring. Any ideas on where to look? As you can see in the full printout from the intermod tool. There are more that one set of possible offenders. -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of n...@no6b.com Sent: Saturday, March 07, 2009 3:47 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Understanding Intermod At 3/7/2009 08:59, you wrote: I did a analysis on a transmitter site using the TCS intermod tool to see what mixes could be causing some issues at this site. I ran the 1-3 order and 1 to 5 order. So I do not use these tools much and was wondering if any of my fellow engineers on here have used this tool and have comments on the output. For example this line from the output confuses me: A+B+C-D-E: 146.7 + 145.77000 + 145.09000 - 145.73000 - 145.73000 = 146.10 It is a hit right on the input but how do you minus 145.73 twice? Is this just an issue with the program I am using? I should say 146.700 + 145.770 + 145.090 - 2 * 145.730 = 146.100 It's actually an A+B+C-2D mix. Bob NO6B Yahoo! Groups Links Yahoo! Groups Links Checked by AVG - www.avg.com Version: 8.0.237 / Virus Database: 270.11.9/1989 - Release Date: 03/07
Re: [Repeater-Builder] Understanding Intermod
Kevin, I recall a case where several UHF community repeaters were installed at a single site. This was not a pretty picture since there was no way to achive vertical seperation and transmitter combiners/receiver multicouplers were not as popular as they are today. An intermod study weas run on the site and at either the 5th or 7th order, every receiver on the site should have been experiencing intermod from a combination of all the transmitters. Of course this was not the case. It was just the program spitting out all the possible combinations that COULD cause a problem. All intermod programs just do the mathmatical combinations and report the outcomes, even outragous ones that are not likely to naturally occur. Some do a better job than others of taking into account things like receiver bandwidth and other factors. Actually finding the source where the mix is taking place much more difficult. The benefit of such programs is that they can easily do the math for you, but you have to decide which numbers are good possibilities and which ones are red herrings. Milt N3LTQ - Original Message - From: Kevin King kc6...@comcast.net To: Repeater-Builder@yahoogroups.com Sent: Saturday, March 07, 2009 8:59 PM Subject: RE: [Repeater-Builder] Understanding Intermod Bob Ok so much for the software. One other user today mentioned a possible issue with another repeater. 147.300. All I had been looking at with the software were the transmitters at his site. Ok so I plug that into the mix of xmiters in the software and bingo. A+B-C 146.70 + 146.70 - 147.30 = 146.100. The repeater 146.70 does have a circulator. Again this intermod is not my best area. I had the repeater owner keep the 146.700 xmitter up them had him hit the 147.30 with an HT and yep we got a burp of noise. But he heard at least 3 repeaters come up. So if this mix is the one that is causing all the issues, now we just need to find where the mix is occurring. Any ideas on where to look? As you can see in the full printout from the intermod tool. There are more that one set of possible offenders. -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of n...@no6b.com Sent: Saturday, March 07, 2009 3:47 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Understanding Intermod At 3/7/2009 08:59, you wrote: I did a analysis on a transmitter site using the TCS intermod tool to see what mixes could be causing some issues at this site. I ran the 1-3 order and 1 to 5 order. So I do not use these tools much and was wondering if any of my fellow engineers on here have used this tool and have comments on the output. For example this line from the output confuses me: A+B+C-D-E: 146.7 + 145.77000 + 145.09000 - 145.73000 - 145.73000 = 146.10 It is a hit right on the input but how do you minus 145.73 twice? Is this just an issue with the program I am using? I should say 146.700 + 145.770 + 145.090 - 2 * 145.730 = 146.100 It's actually an A+B+C-2D mix. Bob NO6B Yahoo! Groups Links Yahoo! Groups Links
Re: [Repeater-Builder] Somewhat OT - How to make HDTV *really* work
One of the biggest problems that is that the current DTV TRANSITION channelization can easily have a VHF analog broadcasting the DTV digital on a UHF channel. POST-TRANSITION the DTV digital could either end up back on the existing VHF channel or on the current UHF transition channel or a new VHF orUHF channel...BUT from the USER point of view the channel number will not change! Thus a channel 4 analog might be broadcasting digital on channel 45 pre-transition and end up on channel 20 post transition; but the channel you would enter on the TV will still be channel 4-1, 4-2, etc. Talk about confusion! It will take at least a generation to straighten this mess out IF over the air television survives. Milt N3LTQ - Original Message - From: JOHN MACKEY jmac...@usa.net To: Repeater-Builder@yahoogroups.com Sent: Monday, February 23, 2009 2:51 AM Subject: Re: [Repeater-Builder] Somewhat OT - How to make HDTV *really* work If the digital is on a very different frequency, then the frequency change is a reason why digital reception may be problematic. For example, if you are using a VHF antenna to try to receive a UHF digital signal, that will be problematic. -- Original Message -- Received: Sun, 22 Feb 2009 09:14:14 PM PST From: wd8chl wd8...@gmail.com To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Somewhat OT - How to make HDTV *really* work That's the gripe. If I put up an antenna that works fine for analog, there is no excuse for it NOT to work with digital, except that digital must be crap. Rf is RF. Virtually everybody I have talked to has had nothing but problems with DTV. Invariably they get fewer channels, and stations that are good to excellent in analog can frequently be unwatchable in digital. To see a digital as reliably as an analog is the exception, not the rule. Yahoo! Groups Links
Re: [Repeater-Builder] Audio Intelligence Devices BXR-2200A Briefcase Repeater
I believe that you now have a nice Haliburton aluminum briefcase. Perhaps a DC power supply. The duplexer might be usable as some sort of filter for reception in the high VHF range Unless you are licensed for something in the high section of VHF the rest is just a pile of parts. Of course you can spend a lot of time finding that out the hard way. Milt N3LTQ - Original Message - From: David Little dalit...@bellsouth.net To: Repeater-Builder@yahoogroups.com Sent: Thursday, February 19, 2009 10:21 AM Subject: [Repeater-Builder] Audio Intelligence Devices BXR-2200A Briefcase Repeater I am looking for any info on an Audio Intelligence Devices (AID) BXR- 2200A briefcase repeater Anyone here have any experience with this, or a pointer on where to look on the web for info? It is a 3 channel, 4 mode setup that operates at 2 and 6 watts with a carrier time-out option for modes 3 (2 watts) and 4 (6 watts). Modes 1 and 2 are the same power without the timeout. The unit is in a Zero Centurion Haliburton aluminum briefcase, operates from internal AC Supply, or external DC source (which both charge the internal Gel Cells when connected) It uses Phelps Dodge duplexers; model number unknown I got it with the intentions of trying it on 2m(600KHz split), MARS or CAP (4 to 5 MHz split) 143 / 148. Any Info appreciated, David KD4NUE Here is a rundown on basic info from looking at the unit. Can send pics (inside and out) if it will help. *** BXR-2200A SERIAL NO 11xx Audio Intelligence Devices Ft. Lauderdale, Florida Gell Cell GC1260 12 Volt 6 Amp (2 pieces) Channel Frequencies: T1 173.8875 T3 R1 165.2875 R2 165.9125 R3 RX Crystal Info: 71.9437 Channel 1 165.2875 (X2+21.4=165.2874) 72.2562 Channel 2 165.9125 (X2+21.4=165.9124) TX 19.3208 Channel 1 173.8875 (X9=173.8872) PA: MHW602 Motorola Brick VHF PA power module Zo OHMS - 50 DC Volts12.5 BW MHz146-174 Max BW140 - 180 P Out Min W 20 P In mW 175 Bias Class C Case 297-02 Frequency Search Yields: Alcohol, Tobacco Firearms 165.2875 r/s Operations (primary) 166.5375 r/s Operations 165.9125 s Unit to Unit 173.8875 s Unit to Unit Yahoo! Groups Links
Re: [Repeater-Builder] Written standard for installs at radio and cell sites?
Robert, What you are hearing about is the Motorola R56 standard. R56 defines everything about a site install including the type of road to provide access to the site. It is a bit old these days having not been updated within the last few years. Once you get past the realization that not everything can be built to the desired standard there is some very good information that can be found in the document, which should be available on a Google search. In the end, the standards for installation at a site are determined by the site owner. If the owner has no standards, then you are entering a very low value site. One example is the site grounding. If the site has unified standards for grounding that everyone adhears to, then the site will be well protected to withstand a strike or near miss. If everyone does their own thing, you will spend a lot of time chasing down gremlins and repairing damages even if your equipment is properly grounded because the whole site is no better protected than the worst case of grounding at the site. Since you have someone who knows what is expected, he should probably be the one to guide the group and share his knowledge by inspecting the equipment before it is taken to the site for installation. Milt N3LTQ - Original Message - From: georgiaskywarn kd4...@juno.com To: Repeater-Builder@yahoogroups.com Sent: Monday, January 19, 2009 9:07 AM Subject: [Repeater-Builder] Written standard for installs at radio and cell sites? Hi Folks, Is there such a beast? We are getting ready to move into a new site and will be installing everything from installing antennas, hardlines to the repeaters. One of the fellows in our ham group does this for a living, however that doesn't help me and the other fellow dressing out the repeaters...in the cabinets, in our own hamshacks before. The term Motorola Standard keeps being used. Anyone heard of this? I know there are certain electrical codes that must be followed...but Moto Codes? I have a 6ft cabinet on wheels right now. It was mentioned that the cabinets must be bolted to the floor. Hoping that I do not have to take the wheels off (real heavy!). Also hoping just to use some sort of J hook to make that happen...but not sure if it is code. Also with the other cabinet we're putting in...we were told it is not code to mount the cans on the outside of the cabinet. Is there something written on the web folks could point us to? Thanks, Robert Burton KD4YDC DEC NWS / Peachtree City, GA Skywarn www.georgiaskywarn.com Yahoo! Groups Links
Re: [Repeater-Builder] Lunch Box Radio
PortaMobile series 2 was based on the GE PE series portables. ICM or Bomar should be able to do the rocks. Batteries or a power supply will most likely be the problem although the supply of parts for the portable on which the radio is based is limited. Good luck it's a nice piece of history. Milt N3LTQ - Original Message - From: Radio Guy ve3...@gmail.com To: Repeater-Builder@yahoogroups.com Sent: Friday, January 16, 2009 10:40 AM Subject: [Repeater-Builder] Lunch Box Radio Any one familiar with the GE Porta Mobile two? It is a low band radio, and I would like to have it converted to the 6m band. I send it to a local shop that was familiar with GE products back in the day, they say it is in very good shape. Any ideas on a company that could make the crystals? Is this a worth while project? Showing hams this radio always brings a smile to their faces,a portable radio that is bigger then most HF mobiles! The tech said... if we need to change out caps, it would be a job for younger eyes! -- --- Ken Yahoo! Groups Links
Re: [Repeater-Builder] Lunch Box Radio
Actually, one other item to consider; make sure that the radio is in the highest bandsplit for a conversion to 6meters. Otherwise it will be a painful attempt to convert. It's been too long to remember if there were just 3 bandsplits or more. Milt N3LTQ - Original Message - From: Radio Guy ve3...@gmail.com To: Repeater-Builder@yahoogroups.com Sent: Friday, January 16, 2009 12:45 PM Subject: Re: [Repeater-Builder] Lunch Box Radio The Ge shop told me that he has some test connectors, for alignment purposes, and I would have to use a different type of battery. Since the battery case was modified, I may be able to fit a sealed lead acid in the overblown case. Interestingly, the Motorola tech just dropped by looking for connectors, and I mentioned the crystals to him, he makes regular orders of crystals and is interested in obtaining the rocks for me. So far all is going well. Any yes, it is a historic piece of equipment, people whom recognise the low band radios have stories to tell about firefighters preferring the long range of heavy radios. On Fri, Jan 16, 2009 at 10:17 AM, Milt wrote: PortaMobile series 2 was based on the GE PE series portables. ICM or Bomar should be able to do the rocks. Batteries or a power supply will most likely be the problem although the supply of parts for the portable on which the radio is based is limited. Good luck it's a nice piece of history. Milt N3LTQ -- --- Ken Yahoo! Groups Links
Re: [Repeater-Builder] motorola repeater cable problem
Dan, From your message I am guessing that you are trying to set up a crossband repeater from VHF to UHF. Otherwise you will need to explain 2 mobiles and a simplex repeater. The rear 16 pin connectors have some pins that are fixed in function (mic audio, PTT, Gnd) and some that are assigned via software (type of audio output, indication of valid PL/DPL/carrier detection). The switching functions must be configured to be active atthe proper level (High or Low). Both radios will need to be properly configured. The configuration of the cable must be bi-directional; it must pass the COS, PTT, and audio signals in both directions, GND is comman between both units. Without the proper equipment and software to program the radios and documentation of the radio and the cable it's going to be rather hard to get things properly set up. Milt N3LTQ - Original Message - From: dan d dwd71...@yahoo.com To: Repeater-Builder@yahoogroups.com Sent: Tuesday, January 06, 2009 9:30 AM Subject: [Repeater-Builder] motorola repeater cable problem I have two Motorola sm50 mobiles using a repeater cable that goes between the two at the option plug in the back. I have tried every configuration two get this to work with no results. Before I condem the cable I got off ebay does anyone know of any mods or settings that need to be done to get this simplex repeater up and running. I have confirmed the radio operation itself and they are good to go. Yahoo! Groups Links
Re: [Repeater-Builder] Triplett 630 Multimeter
John, Is it possible to post the link to the group? That way anyone can go and find the site. If not my address is below. Milt N3LTQ n3...@yahoo.com - Original Message - From: John J. Riddell To: Repeater-Builder@yahoogroups.com Sent: Thursday, January 08, 2009 4:56 AM Subject: [Repeater-Builder] Triplett 630 Multimeter Triplett 630 Multimeter I came across the manual for the Triplett 630 Analogue Multimeter on the Internet in PDF format, and if anyone needs it I can send it to them. It's about 30 pages if you print it. John VE3AMZ
Re: [Repeater-Builder] DB4062 in non-standard application
Scott, IIRC the split on a CAP repeater is very wide; one side is below the 2 meter band and the other is above...148.15 as an output comes to mind with a 143 input. That being the case I would suspect that they probably reconfigured the duplexer to use 1 or more cans for the packet freq and the rest for the repeater since the wider split would not require all 6 cans for proper isolation. Sounds like a trip to the site would make for an interesting snowmobile run. Milt N3LTQ - Original Message - From: Scott Zimmerman n3...@repeater-builder.com To: Repeater-Builder@yahoogroups.com Sent: Thursday, January 08, 2009 4:19 PM Subject: [Repeater-Builder] DB4062 in non-standard application The local CAP group has a DB4062 duplexer. (6- 8 cans) Somehow they are able to operate a VHF repeater and a packet node all on one antenna using this set of BPBR's. Does anyone have an idea as to how they would have plumbed the duplexer to make this happen? I don't know the CAP frequencies in question, sorry. I would like to do a 2M machine - 147.075+ and APRS - 144.39. I realize I *could* just go to the site and look, but it's at about 3000' and it's snowing like crazy right now. This is not to mention the ICE we had the past two days. Scott Scott Zimmerman Amateur Radio Call N3XCC 474 Barnett Rd Boswell, PA 15531 Yahoo! Groups Links
Re: [Repeater-Builder] Problem remote base linking of 2 repeaters using CAT 300 DXL controller
Chris, To start with you will need to give us much more information, but I think that one possible question that immediatly jumps into my mind is that of isolation between the 2 meter remote bases. As I read your post you have a 440 repeater with three 2 meter radios, all at the same site. I'm assuming that each 2 meter link is set up on a single frequency pair. When you are using only one 2 meter radio everything works OK. When you bring on a second 2 meter radio the system hangs in transmit. My questions to start with would be: 1) How much vertical distance is between the antennas for each of the 2 meter radios? 2) What kind of antennas (omni or beam) on the 2 meter links? 3) What kind of equipment is in use for the 2 meter links? 4) Is there any extra RF filtering in use on any of the 2 meter links? 5) Have you been at the site and tried to listen to the 2 meter radios to see if any of the combinations of transmit and receive cause any of the other link radios to unsquelch? 6) Do the links use carrier squelch or PL? Milt N3LTQ - Original Message - From: w4vx_chris w...@charter.net To: Repeater-Builder@yahoogroups.com Sent: Monday, December 29, 2008 2:40 PM Subject: [Repeater-Builder] Problem remote base linking of 2 repeaters using CAT 300 DXL controller Fellow repeater builders, I am a relative novice at repeater linking and need some trouble shooting/system design advice. I have a 440 repeater with 3 two meter remote base radios tied together using the CAT 300 DXL controller with the RLS board. The remote base radios are tuned to local repeaters that we would like to link together. Individually, each remote base radio works fine meaning I can turn it on with via 440 repeater and qso on the target repeater. Also, another local repeater with a 440 remote base is able to link the 440 repeater and when I turn on one of the remote base radio and link in another 2 mtr repeater it works fine (repeater key up and down like one big repeater). The problem arises when I try to use the two or more 2 mtr remote base radios to link two 2 mtr repeaters together. The system comes up stays up - never unkeys. Is this a hang time issue? Or is there something wrong about trying to link two repeaters on two meters with 2 meter remote bases through a 440 machine - usually folks target the 440 repeater with a remote base not the other way around? Could it be a controller setting issue? I am really stuck at the moment and I appreciate any thoughts you may have. It sure would be nice to have these repeaters linked for our nets and is generally kinda cool if we can pull this off. Vexed in Virgina, Chris W4VX Yahoo! Groups Links
Re: [Repeater-Builder] VHF Unified Chassis Micor
Service manual and o-scope for signal tracing Milt N3LTQ - Original Message - From: Terry wx3m.te...@gmail.com To: Repeater-Builder@yahoogroups.com Sent: Monday, December 29, 2008 4:22 PM Subject: [Repeater-Builder] VHF Unified Chassis Micor From retired parts, I am attempting to assemble a VHF Micor Unified chassis into a repeater. I already succesfully assembled the UHF model. I can not under any circumstances get any local speaker audio from the VHF chassis. The receiver is working and producing discriminator noise, measured at receiver pins 15 and 16.and on meter position 5. The audio squelch board works in another station. The audio pass board is good.(tried 2 other working parts from mobiles) Jumpers 1, 4, and 5 on the TLN 5644 backplane are in. J5-14 is jumpered to J5-19 On the backplane board, where the 30 receiver interconnect board pins come through, pin 6 to 14 in jumpered. J2 19 is jumpered to 20 What say you? Thanks, Terry Yahoo! Groups Links
Re: [Repeater-Builder] Six Meter Repeater Noise Issues
A similar war story from back in the early 90's...Commercial customer with a 35MHz base complaining of dramatically reduced range. Base and mobiles checked out fine, antenna system fine, just trouble receiving the mobiles. Dropping the PL with the antenna connected I noticed what seemed to be a constant carrier. A bit of wandering about with a scanner using increasingly short lengths of wire for antennas brought me to a nearby house. The noise seemed to be radiating on the telephone line and the power line. The house was a rental owned by the company with the radio so after proper contact was made an inside sweep found the ... telephone answering machine!?!?!?! The device was powered by a wall wart supply with an very long cord (getting any clues yet?); which had recently come back from a repair center. The wall wart had a slightly audible hum. A snap together ferrite with as much of the excess power wiring wound onto the ferrite as possible, and another ferrite on the telco line brought the noise to a level that was not detectable at the base station. Milt N3LTQ - Original Message - From: neal Newman To: Repeater-Builder@yahoogroups.com Sent: Friday, December 26, 2008 9:39 AM Subject: Re: [Repeater-Builder] Six Meter Repeater Noise Issues Noise on the six meter repeater. On my machine 53.67 in New jersey I was getting noise that was holding the machine Keyed up. then drop. and key up again. I thought it was desense Even with a big expensive Commercial Duplexer. with the transmitter off, the normal unsquelched Hiss sounded Fine No noise that we could detect. after weeks of this. We finally found out what the Problem was. the 2 meter,and 440 machines next to it ran just fine.however They both had an IRLP link on them. The Noise problem turned out to be the Router/switch. The Noise it was creating was just at the threshold level to Key and hold open the repeater. BTW. The 6 meter machine was in PL with a Tone of 67hz.. Not a good choice. between the60 cycle noise of a bad wall wart for the router switch and the noise it created. might as well put a flea power transimitter with PL sitting on the repeaters input. changed the router swich and PL tome. and Problem wentt away. Verizon uses cheapo routers. we placed the new one in a shielded box Neal-KA2CAF --- On Thu, 12/25/08, Mike Morris WA6ILQ wa6...@gmail.com wrote: From: Mike Morris WA6ILQ wa6...@gmail.com Subject: Re: [Repeater-Builder] Six Meter Repeater Noise Issues To: Repeater-Builder@yahoogroups.com Date: Thursday, December 25, 2008, 10:12 PM At 11:06 AM 12/25/08, you wrote: Hi To All Hope everybody had a good Christmas, While the subject was brought up, I have been having a similar experience here at my location. It is not on a repeater, but a simplex radio (vertex VX3000l mobile) for a base on the natl Red Cross freq of 47 mhz. In the daytime the receiver is quiet and hears fine. It seems as about the time the sun starts going down, the receiver's squelch opens and has a constant static noise for many hours but still receives fine. It may do it all night, I don't know, I haven't stayed up to see, just leave the radio on and go to bed. Was wondering if could be power line noise (but why wouldn't do in daytime also)? Is there any interference to the HF bands like this at night? Thanks, Mike KB5FLX An old trick - if the on-time changes about 6 minutes a day then it's light-dependent (i..e a photo-electric triggered yard light). In your shoes I'd power the radio from a gell-cell, and then go flip breakers off one at a time. That will tell you if the noise source is inside the house, and if so, on which breaker. Mike WA6ILQ
Re: [Repeater-Builder] RE: What Have I got and can I get information about it.
The question is frequency stability for fixed stations. If the unit is operated as built (minus the phone patch) vs the possible use of an external amplifier as mentioned in the original post. Just because the portable on which the unit is based is type accepted for portable use, the use of the same radio in a fixed station configuration could possibly fall under a different set of standards. Be sure to consult the appropriate sections of the current version of Part 95. MIlt N3LTQ - Original Message - From: Craig W Clark To: Repeater-Builder@yahoogroups.com Sent: Thursday, December 18, 2008 2:35 PM Subject: RE: [Repeater-Builder] RE: What Have I got and can I get information about it. Huh? Since when is a GP300 not type accepted for GMRS? News to me, but I have been wrong before. (once!) -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Milt Sent: Thursday, December 18, 2008 2:12 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] RE: What Have I got and can I get information about it. Rick, The Systel was a 2 watt repeater with a telephone interconnect designed for small on-site systems. I doubt that it would be type accepted for GMRS as it was based on one or more series of portables (HT-90 and/or GP300). Of course the phone patch would not be usable on GMRS either. MIlt N3LTQ - Original Message - From: Rick Beatty To: Repeater-Builder@yahoogroups.com Sent: Thursday, December 18, 2008 12:37 AM Subject: [Repeater-Builder] RE: What Have I got and can I get information about it. I recently was given a SYSTEL unit made by Motorola, on 464.../469... with duplexer and looks to be a repeater, with low level output (2w or so). Would be great for remote work on GMRS, does anyone on the group have data/information on this little cutie? Also I am looking for a schematic for an amplifier used with the portable. a UHF with the number N1275a? thanks in advance -- Rick
Re: [Repeater-Builder] RE: What Have I got and can I get information about it.
Rick, The Systel was a 2 watt repeater with a telephone interconnect designed for small on-site systems. I doubt that it would be type accepted for GMRS as it was based on one or more series of portables (HT-90 and/or GP300). Of course the phone patch would not be usable on GMRS either. MIlt N3LTQ - Original Message - From: Rick Beatty To: Repeater-Builder@yahoogroups.com Sent: Thursday, December 18, 2008 12:37 AM Subject: [Repeater-Builder] RE: What Have I got and can I get information about it. I recently was given a SYSTEL unit made by Motorola, on 464.../469... with duplexer and looks to be a repeater, with low level output (2w or so). Would be great for remote work on GMRS, does anyone on the group have data/information on this little cutie? Also I am looking for a schematic for an amplifier used with the portable. a UHF with the number N1275a? thanks in advance -- Rick
Re: [Repeater-Builder] Mitrek
Comm Spec has a prewired cable available. See http://www.com-spec.com/insheet/mitrek2.pdf Milt N3LTQ - Original Message - From: Randy k8kh...@earthlink.net To: Repeater-Builder@yahoogroups.com Sent: Sunday, December 14, 2008 10:27 PM Subject: [Repeater-Builder] Mitrek At 05:58 PM 12/14/08, you wrote: Can any one tell me where I can find a cable for a TS64 to a Motorola Mitrek Randy Build it yourself. The full TS64 data package is on the Com-Spec page at www.repeater-builder.com and the Mitrek info is there as well (I put it there after a bunch of folks asked for it after reading my Mitrek Interfacing writeup). Mike WA6ILQ Mike We looked at the information on www.repeater-builder.com before posting this message problem is by the time we buy the plug for the radio and the ts64 buy the wire and what ever else we need I would be better off to simply buy it. We used to make all of this stuff but things change. Randy Yahoo! Groups Links
Re: [Repeater-Builder] Two UHF Repeaters - one antenna
Is there any possibility of reversing the TX and RX frequencies of the FM analog repeater? Milt N3LTQ - Original Message - From: Mike Mullarkey To: Repeater-Builder@yahoogroups.com Sent: Sunday, November 16, 2008 12:07 PM Subject: RE: [Repeater-Builder] Two UHF Repeaters - one antenna David, I would say this could be easy but since you have you have a 1.6Mhz split on the Voice repeater it will be tough with one antenna. You are going to have to use ¾ wave cavities for the transmit combiner and a lot of loss. I could not this working out unless you have a hybrid combiner and other items. If you can add another antenna it is a slam dunk as long as you have 30ft of separation between the TX RX Antennas. Mike K7PFJ -- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of dlake02 Sent: Saturday, November 15, 2008 10:04 AM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Two UHF Repeaters - one antenna Hello I need some advice - I've searched the group and can't find an answer, so I call on the collected wisdom here, but apologise in advance for taking your time. I have a repeater site that has a single antenna, VHF and UHF. Now, combining the VHF and UHF is fine, although lossy. But, we want to add D-Star at 70cm, which means that I will have two UHF repeaters, two sets of cavities. How do I combine the output of the two cavities prior to feeding to the VHF/UHF combiner ? My frequencies are close: D-Star TX 439.6125 FM RX 434.650 FM TX 433.050 D-Star RX 430.6125 Do I just couple to another T-piece ? Are the cable lengths critical ? Has anyone got experience of doing this ? Thanks in advance for your assistance. David - G4ULF
Re: [Repeater-Builder] MTR2000 UHF Service manual
For the benefit of everyone on the list let me advise all of you concerning the new world of Motorola service; at least when compared to the old days when the MSF5000 was considered the top of the line and the days of antiquity when the Micor was king. I will not even try to find adjectives to describe the days of the Motrac as the king of the hill as most Motorolans today have no idea what a Motrac was. ***Disclaimer*** What follows is personal opinion and in no way reflects the views of the list owners or others on the list. It is also not a timeline. When Motorola created the MSF5000 they crossed over from the conventional crystal based designs of many years to a new world of microprocessor based design. The letters MSF stood for Maximum Station Flexability and the MSF was a very capable station. By using software or the R1800 programmer the parameters could be changed easily in the field, repeatedly. It covered wide swaths of RF spectrum in a single radio. Along with the other microprocessor based radios that Motorola was developing it completely changed the direction that most radio shops were going. The new world of radios created a servicing nightmare. The guy on the bench who had been dealing with crystal based designs and leaded componets all his life now had to decide to either update his skills or maybe look elsewhere. A lot of turnover started to take place in the service environment. And then there was that part about being on a mountaintop with a non functioning radio; how did you drag all the items needed to troubleshoot and repair a PLL circuit based radio with you? Or did you drag the station back to the shop? Motorola made a decision that the generation of station equipment that followed the MSF5000 would be based on the concept of Field Replacable Units. Basically break the radio down into building blocks that can easily be swapped out wherever theradio is located with a minimum amount of effort and equipment. Thus the Quantar radio was designed to be a series of modules in a backplane. Initially no service information was released beyond simple, basic in/out diagrams. A similar philosophy holds true with the MTR2000 radio and will, I am sure, continue into the future. One reason is the complexity of the circuitry and the extensive use of leadless componets and new generation chips which combine a multitude of functions in a single device. Another is the need for specialized test and rework equipment in order to even attempt to troubleshoot or repair the circuit boards. As Eric pointed out, you can procure a Depot level manual from Motorola which will have all the required information and schematics. If you are equipped to deal with high density surface mount rework, then go for it. Otherwise there is the depot. Good Luck Milt N3LTQ - Original Message - From: Camilo So To: Repeater-Builder@yahoogroups.com Sent: Monday, October 20, 2008 9:15 PM Subject: Re: [Repeater-Builder] MTR2000 UHF Service manual Oh I forget to mention that I did order a service manual from Motorola 6681096E25 its don't have any circuit diagram on it, What is the correct manual number to order that have a circuit diagram. - Original Message - From: Camilo So To: Repeater-Builder@yahoogroups.com Sent: Monday, October 20, 2008 9:08 PM Subject: [Repeater-Builder] MTR2000 UHF Service manual Need help to order a MTR2000 service manual that have the schematic diagram of the receiver unit, Got this unit from Ebay, Hook up the unit on my bench with a dummy load on the TX out, and apply signal on the RX input with a IFR1200, The squelch open at 0.12 micro-volt at 0.15 uv its 12 DB Sinad, when signal was increased to about 1.0 micro-volts or higher the receiver drop out, as if the agc is overloaded that cut out completely and also drop the TX, Have anyone ever experience this problem before, This is the first time I have seen this kind of problem , and its hard to fix it w/o a diagram. any help is highly appreciated. de w4cso Camilo
Re: [Repeater-Builder] Motorola CDM-1250 PL tone control
Look at the help files accompanying the CPS program, especially the ACCESSORY Configuration tab, ACCESSORY Connector for pin definitions and the ACCESSORY Pins Tab. Also look at the manuals for the i20 repeater controller and the Z340 Comunity repeater controller. One of the options on several of the pins is TX PL DISABLE (INPUT). Definable as High or Low for active level. Milt N3LTQ - Original Message - From: James Adkins To: repeater-builder Sent: Monday, October 13, 2008 3:10 PM Subject: [Repeater-Builder] Motorola CDM-1250 PL tone control We are using a pair of Motorola CDM-1250 UHF mobiles, 403-470 split, for our UHF repeater along with an Arcom RC-210 controller. We want to strip the PL tone when CW and / or Voice ID's are sent. The arcom controller has the capability of sending logic out to the radio or an external tone board to turn the encode on or off. Does anyone have any knowledge of how one might be able to inject the CTCSS logic into the 16-pin accessory port, or otherwise connect to the CDM radio and control whether the CDM will encode our PL tone or not? Another option is the CommSpec SS-64, which I have on hand. However, we cannot simply parallel the tone output into the pre-emphasized audio input of the radio. I know that the radio could probably be programmed for no pre-emphasis, but I don't want to bypass limiting. Ideas or suggestions? Maybe someone knows a good location to inject the tone directly into the radio's modulator? Thank you, James Adkins, KB0NHX [EMAIL PROTECTED] -- James Adkins, KB0NHX District 1 Technical Field Engineer Troop A--Lee's Summit; Troop H--St. Joseph Missouri State Highway Patrol 504 SE Blue Parkway Lee's Summit, MO 64063 816-622-0707 ext. 235 417-840-5261 (Cell) I'm James Adkins and I approve this message
Re: [Repeater-Builder] Zetron SCU controller
Lots of equipment can encode the 2+2 Quick Call format but since today's decoders are software based (counting squared off audio waveforms) instead of hardware based (mechanical reeds) nothing I have seen recently will accurately decode the format. Milt N3LTQ - Original Message - From: [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Saturday, October 11, 2008 6:37 PM Subject: Re: [Repeater-Builder] Zetron SCU controller Hi Ian, Does anyone have any info on the unit in question that generated those tones? I'd love to find one - just for memorabilia. That tone format has been around for a long time in mobile radio (Motorola Quik-Call I) and is still being used in aviation (ICAO SELCAL) to page aircraft on the company channel. A chime informs the flight crew that a message follows (in case the volume has been turned down -- it happens when you have three radios going... :-). Aviation uses SELCAL on VHF-AM and HF channels, but on HF the tones are sent with amplitude modulation to ensure proper decoding while the conversations take place on SSB. Our air/ground interconnect and 7330 repeater controller support SELCAL because commercial customers still use it. 73, Bob Bob Schmid, WA9FBO, Member S-COM, LLC PO Box 1546 LaPorte CO 80535-1546 970-416-6505 voice 970-419-3222 fax www.scomcontrollers.com -- New MapQuest Local shows what's happening at your destination. Dining, Movies, Events, News more. Try it out!
Re: [Repeater-Builder] LMR-400 Cable
The next step in your troubleshooting would be to move that dummy load to the other end of the coax and repeat the desense test; that checks your coax and duplexer. If everything checks OK then move on to substituting a different antenna. I would suggest that you construct a basic ground plane antenna and try that in place of the Diamond antenna. Milt N3LTQ - Original Message - From: Tom Elmore To: Repeater-Builder@yahoogroups.com Sent: Wednesday, October 01, 2008 1:06 PM Subject: [Repeater-Builder] LMR-400 Cable I recently put a six meter repeater (52.810/51.110) on the air here in Anchorage, Alaska. I am feeding it with about 60 feet of LMR-400 cable and am experiencing quite a bit of desense. I did a search for LMR-400 in duplex operation and came across several posts from users of this list and decided to sign up and investigate some more. I am running a GE Master Pro at 100 watts into a 8 cavity Sinclair duplexer. The antenna is a Diamond co-linear mounted about 35 feet above ground at the present time. I live on a hill here in town and currently have the repeater mounted at my home qth. When I terminate the duplexer into a dummy load and look at it with the spectrum analyzer it performs very well with no desense. Connecting up the antenna is another story altogether. I have been pulling my hair out over this one thinking it must be a duplexer problem. Originally I fed the antenna with RG-213 which I know is not the best choice for repeater use but it is what I had handy at the time. I was getting desense with the RG-213 so I switched to the LMR-400 since I had a roll someone had given me. I actually think I had slightly less desense with the RG-213. Is the 400 really not that suitable for duplex operation even at 6 meters? What would be a good alternate choice ? Thank You Tom Elmore KA1NVZ Anchorage, Alaska
Re: [Repeater-Builder] LMR-400 Cable
Decibel made a low band duplexer that used notches made from helical resonators and passes made from lengths of coax. The whole thing measured maybe 3.5 ft Hi x 2.5 ft wide x 8-10 deep and could mount on a wall. I suspect his Sinclair is the same sort of thing. I recall talking to an engineer at Decibel about retuning the notches and he said that large frequency changes would require opening the cans and doing major surgery. Milt N3LTQ - Original Message - From: Chuck Kelsey [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Thursday, October 02, 2008 8:06 PM Subject: Re: [Repeater-Builder] LMR-400 Cable I suspect that he has notch cavity resonators. Each can is about two feet tall, more or less. So, while eight of them take up some space, they are not likely as large as you envision. Chuck WB2EDV - Original Message - From: [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Thursday, October 02, 2008 7:14 PM Subject: Re: [Repeater-Builder] LMR-400 Cable Tom, With 65 feet of cable, your feed line is very close to a resonant length at 6 m. Actually about 3 wavelengths. If you have enough extra coax length, try winding some of it into a coil and see if that reduces your desense problem. Also, make sure your antenna is a good impedance match to your transmitter/duplexer impedance. A 6-cavity duplexer on 6 m has to be a HUGE duplexer and I suspect that's where your problem is. You have to have a VERY precisely tuned duplexer that provides at least 85 dB of isolation between the XMTR and the RCVR. 73, Dick W1NMZ Yahoo! Groups Links
Re: [Repeater-Builder] Re: Update on the MICOR Community Repeater project
The Diode Logic Module and Multiple TPL Encoder cards would only have been used if someone wanted to RX one PL code and TX another, ie crosscoding, a rare beast indeed but Moto had the capability... Milt - Original Message - From: wd8chl [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Tuesday, September 23, 2008 5:27 PM Subject: Re: [Repeater-Builder] Re: Update on the MICOR Community Repeater project Joe Burkleo wrote: Mark, Sorry to hear that you are still fighting this problem. I think we were on the right track when this kinda ended last month, in that what you need to find is a Motrac series community repeater manual that might show the TLN5803A Master Decoder. I have not been able to turn one up yet. I do have one question for you about the original configuration in these stations. Did they originally have a Diode Logic and a Multiple TPL Encoder card installed in them? I am sure you have answered this question already, but I really do not remember. I have never seen those cards in any Micor CR's I looked at, so I'm certain they are not necessary. I think the right path is that he has MSY Master decoder cards, and I know they are not directly compatible. But I think they can be modded... Yahoo! Groups Links
Re: [Repeater-Builder] Motorola MICOR Receiver enclosure questions
Sounds like the 72 MHz RX option for the PURC 5000 series radio. A seperate manual as I recall. Try Moto parts ID for more info. Milt N3LTQ - Original Message - From: [EMAIL PROTECTED] [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Sunday, September 21, 2008 1:35 PM Subject: [Repeater-Builder] Motorola MICOR Receiver enclosure questions I recently picked up a 72-MHz MICOR receiver off of the big auction site (won't mention the name lest someone get all [EMAIL PROTECTED]!).. This MICOR receiver appears to be in a 3-1/2 high MSF-5000 series box, with the spring-loaded releases on the black front panel. It has a squelch control and an RJ-series jack on the front panel, and the rear panel has a BNC antenna jack, along with a 10-pin male plug. The Motorola P/N stamped on the rear is TRC1072AB, which might be just something like the rear panel number and not the complete assembly number. Does anyone know what series station this receiver was used in? I'd like to find the hookup info for it, and find a part number the 10-pin matching connector. I have plenty of actual MICOR receiver info, for receivers of all bands, and would like to use this as a UHF control receiver for a 2-Meter repeater. Repeated request for info emails to the original seller have not been responded to, so Im trying here. One person in our shop felt it might be part of an MSF-5000 sereis paging station, with this 72-MHZ receiver used for control (maybe similar to a 330W MICOR PURC station on 42 MHz with its 72-MHz receiver, which I have sitting in my garage.) Larry Yahoo! Groups Links
Re: [Repeater-Builder] Uniden ARU-251
IIRC there is a front panel pushbutton switch which will interrupt the repeat function allowing the unit to act as a full duplex base station (non-repeat). I think it was marked Repeat/Local. Just a guess at this point. Mlt N3LTQ - Original Message - From: Richard Bessey [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Tuesday, August 26, 2008 8:25 PM Subject: [Repeater-Builder] Uniden ARU-251 All, I am hopefull someone can tell me what I am doing wrong. I got a Uniden ARU-251 off of Ebay from a fellow ham, all tuned up and ready to roll as a GMRS repeater form me. All is well, it showed up and had a loose jumper inside, so it was not on the correct PL tone. After some diagnostics, I figured that out, and got the jumper fixed and it was fully operational. I turned it off and went to bed. The next day, I kick it on to play with it, and it won't repeat. I take the cover off and watch the control board, its recieving RX (Per the LED, and I can hear it on the front speaker), Its getting the proper tone (Per the LED), yet it will not TX. Is there any Uniden ARU-251 pros on the mailing list that could tell me what to check/test to find the source the problem. Its gotta be something simple (loose wire, etc...) since one of the jumpers on the control board came loose during shipment. If anyone has any tips I would greatly appreciate any info. Regards, Richard Bessey Yahoo! Groups Links
Re: [Repeater-Builder] Rackmount clips/screws
Now Motorola cabinets on the other hand mostly have 1/4 holes for the tinnerman nuts he was talking about... The current Motorola floor mount cabinets how have rack rails that are predrilled for metric screws. The size is M6x1. The screws are a T30 Torx head and are self threading. Based on a quick check of Lowes' pricing for metric hardware it's cheaper to purchase the self threading screw from Motorola. Milt N3LTQ
Re: [Repeater-Builder] Rackmount clips/screws
Not a bad idea Bob. The Lowes store nearby has M6x1x10 hex heads at 0.23 each. Other suppliers probably have better pricing. Motorola's pricing looks like 0.15 each. Milt - Original Message - From: Bob M. [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Monday, August 25, 2008 11:00 AM Subject: Re: [Repeater-Builder] Rackmount clips/screws I found that it's very easy to use one of the existing M6x1 T30 self-tapping screws to tap any other virgin holes in the rack, then an ordinary M6x1 Phillips-head machine screw can be used in its place. I bought a box of 100 of them from a local hardware company for about $5 and replaced all the missing screws. OK, they're not black, they're not original, and they're not T30, but it's easier to put the new screws into the old holes in the most used locations and just use the Phillips driver from then on. Bob M. == --- On Mon, 8/25/08, Milt [EMAIL PROTECTED] wrote: From: Milt [EMAIL PROTECTED] Subject: Re: [Repeater-Builder] Rackmount clips/screws To: Repeater-Builder@yahoogroups.com Date: Monday, August 25, 2008, 6:38 AM Now Motorola cabinets on the other hand mostly have 1/4 holes for the tinnerman nuts he was talking about... The current Motorola floor mount cabinets how have rack rails that are predrilled for metric screws. The size is M6x1. The screws are a T30 Torx head and are self threading. Based on a quick check of Lowes' pricing for metric hardware it's cheaper to purchase the self threading screw from Motorola. Milt N3LTQ Yahoo! Groups Links
Re: [Repeater-Builder] Curious Situation
No, you just got confirmation that you had the duplexers close to spec, and the cost is not out of line for labor and test equipment if everything was done correctly. You only tuned one piece of the entire system however so there may be other things lurking in the background. Something in one of your reply posts is raising questions however: The antenna is a HyGain V-3 ( this is a temporary antenna that was available for the testing phase ) ground plane which has 2 sets of radials. The antenna is fed with ½ Heliax. The antenna is 30 to 40 feet horizontially separated and 20 ft vertically. ( Not a lot of separation to be sure but again the install at this location is temporary while working the kinks out..). What are you referring to as the seperation? Antenna to repeater? And the dumb question You did verify that all the connections went to the correct ports? Milt N3LTQ - Original Message - From: Michael Ryan To: Repeater-Builder@yahoogroups.com Sent: Tuesday, July 29, 2008 11:37 PM Subject: [Repeater-Builder] Curious Situation Rber's, I posted a note very early this week about my looking for a someplace to get a 220 duplexer tuned in the TAMPA area. Having not much luck I contacted a local MOTOROLA shop and paid $95 for the service. The receipt returned with the cans indicates that the specifications published by WACOM are very close. Having tuned these merely to incoming signals before, peaking them while the repeater is still in a testing mode, seemed to return decent results but the tune-up was thought to be a better idea. Not so.. Today's tune-up hardly was worth the wait or the price based on the results. While a 5 watt HT 10 miles away could work the repeater, now 25 watts from a roof top antenna is now just about full quieting. Fifteen watts does not make the repeater through the same roof top ground plane. Does logic dictate that we go back to seat of the pants tuning and cast fate to the wind? - Mike
Re: [Repeater-Builder] UHF MICOR Unified Chassis
You have what were referred to as Community Repeater stations. Before LTR trunking and 800 MHz there were community or shared repeater stations everywhere used heavily by businesses small and large. There is a seperate manual addition which deals with this station. I'll check my files tomorrow. Basically (going from memory) the discriminator signal leaves the RX and goes to the SQ gate and the Master Decoder. Based on which PL or DPL codes are activated on the Four User Modules the signal is either repeated or ignored. Usually the code that is received is transmitted, however it is possible via the Diode Logic and Multi PL or DPL encoder cards to translate the incoming code to another outgoing code. Milt N3LTQ - Original Message - From: n9wys [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Sunday, July 27, 2008 7:56 PM Subject: RE: [Repeater-Builder] UHF MICOR Unified Chassis I looked at 7 of the 14 chassis I have; the ones I looked at were *all* TRN6421 - including those with what appeared to be the Zetron interface wiring. The labeling for the card cage is as follows (again, listed from right to left): TOT STN CONT SQUELCH GATE SINGLE TONE DECODER MASTER DECODER FOUR USER CONTORL MODULE \ FOUR USER CONTORL MODULE \ FOUR USER CONTORL MODULE Yes, 4 slots labeled the same FOUR USER CONTORL MODULE / DIODE LOGIC MULTI PL ENCODER MULTI DLP ENCODER Mark - N9WYS -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Joe Burkleo Sent: Sunday, July 27, 2008 6:37 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: UHF MICOR Unified Chassis Mark, I agree with Eric, you are aways away from cutting and hacking on traces until we can identify exactly which backplane board you are working with. Most of the time that I have seen the TRN prefix, it usually has been tied to the PURC series of radios. Are all of your backplane boards that you have, this same model number? On the backplane board what are the cards slots labeled as? Knowing this information may help identify what the original station service type was. Joe - WA7JAW --- In Repeater-Builder@yahoogroups.com, n9wys [EMAIL PROTECTED] wrote: OK - I'm now home from work and have had an opportunity to look at the station. The backplane has the following number printed on it: TRN6421A Motorola parts identifies it as: BD INTCONN --- *This item has been cancelled This is all I can seem to find about it right now... And Eric, these are the manuals I currently have: Control and Applications Manuals: 68P81025E60-E and 68P81025E60-F MICOR Base and Repeater Stations Manuals: 68P81025E50-G (12W to 75W stations) and 68P81039E55-A (200W and 225W stations) Mark - N9WYS Yahoo! Groups Links No virus found in this incoming message. Checked by AVG - http://www.avg.com Version: 8.0.138 / Virus Database: 270.5.6/1576 - Release Date: 7/27/2008 4:16 PM Yahoo! Groups Links
Re: [Repeater-Builder] Re: How to figure cable length for duplexer?
Gary, When selecting a duplexer you want a model that is speced for the same TX - RX spacing as the application or less. Operating a 500K spacing duplexer at 600K is not a problem but trying to get a 1M spaced duplexer to operate at 600K will be. The issue is the way the individual pass/notch filters interact with each other. If you can get a copy of a Telewave catalog they have a nice section in the back that gives plenty of information about filters and duplexers. As to your immediate problem, adding a pass can via the proper length of coax on the RX side may help. I would suggest that you look for someone in your region with the proper test equipment to sweep tune the equipment. Also what type of repeater equipment are you using? Milt N3LTQ - Original Message - From: garyp609 [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Friday, July 25, 2008 8:12 PM Subject: [Repeater-Builder] Re: How to figure cable length for duplexer? Thanks for the info. I will call call Telewave for an education. The TPRD1454 shows 77db of isolation and a minimum of a 1 meg split. I am running .600 split here. 73's Gary K2ACY --- In Repeater-Builder@yahoogroups.com, Bob M. [EMAIL PROTECTED] wrote: Telewave is VERY responsive to e-mails and even phone calls. I've had technical questions about their duplexers on several occasions and have sent e-mail to their only public e-mail address. Usually I get a reply later the same day or first thing in the morning from a man named Ray Collins. Turns out he's the president of Telewave and very nice to converse with. Highly recommended. I will offer this, however. Celwave (and possibly other manufacturers) seem to have cut lists which specify the lengths of coax you need between cavities and from the last cavity to the TEE connector. Telewave doesn't seem to have them; I've asked in the past and I'm always told they make each cable set on the shop floor when the unit is attached to expensive analysis equipment, starting with some known (but un-publicized) length, just to get it close, then they trim to fit until the unit performs as they want it to. In actuality, they may have a bunch of cables all made in various lengths by 1/4 inch increments, then select the right ones to get the desired performance. You probably wanted a TPRD1454 unit, if they make one, as that would have the right cable lengths and configuration for the 2 meter band. Bob M. == --- On Fri, 7/25/08, garyp609 [EMAIL PROTECTED] wrote: From: garyp609 [EMAIL PROTECTED] Subject: [Repeater-Builder] Re: How to figure cable length for duplexer? To: Repeater-Builder@yahoogroups.com Date: Friday, July 25, 2008, 7:09 PM Jim, Thanks for the response. The duplexer is a Telewave TPRD1554. They are brand new and bought from Tessco tuned. The cable on the RX side is marked 11 in black marker on the connector and the TX side is marked 11 1/2 . Both cables terminate at the T. I just want to feel assured that they are the right length as I feel my performance should be much better and want to rule out the duplexer. Gary K2ACY --- In Repeater-Builder@yahoogroups.com, Jim Brown w5zit@ wrote: What kind of duplexer is it? I have several older Sinclair 2 meter duplexers that were up in the 170 mHz range that I moved down to the ham band, and I had to replace each 10.5 inch cable that went from the can to the Tee with a cable 12.5 inches long. Turns out for those older models that piece of cable was part of the tuned circuit for adjusting the nulls. All duplexers are not made the same, so I think you need to be more specific. Interesting on the frequency you are using. We are just putting one on the same frequency here in central New Mexico - HI. 73 - Jim W5ZIT --- On Fri, 7/25/08, garyp609 gary.paul@ wrote: From: garyp609 gary.paul@ Subject: [Repeater-Builder] How to figure cable length for duplexer? To: Repeater-Builder@yahoogroups.com Date: Friday, July 25, 2008, 5:46 PM Output frequency is 145.450 input is 144.850. How do I figure out what length the cables should be between the rx side and tx side that connect to the T-Connector? Thanks and 73's ! Gary K2ACY Yahoo! Groups Links
Re: RE: [Repeater-Builder] PL Problem
I second the service monitor check and further suggest that one have the software to program the radio and the tuner software on standby in the PC. While 1K of PL deviation is high it should be decoded unless the radio has been programmed for say, 12.5k bandwidth. Have a look at the programming and you will probably be able to find more of what is going on. Milt N3LTQ - Original Message - From: Ron Wright [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Friday, July 18, 2008 8:10 PM Subject: Re: RE: [Repeater-Builder] PL Problem PL is usually aroung 800 Hz. 1 K little high, but should not cause a problem unless the problem radio's PL circuits are being over driven. I would get the problem radios on a service monitor. Some of the IC PL units, which probably is what is in these radios, and there might be a problem with them not being on PL freq. Generate the input rcv signal with PL from the service monitor and see how far off PL tone freq you can be. Might find they are on the edge decoding sometimes and not others. Also could verify if receivers have a sen problem. With radios in PL it is often harder to tell if signal is fading since PL cuts in and out and cannot open sq for this test. I would want to verify problem receivers are working before I tore into the base/repeater. 73, ron, n9ee/r From: David Murman [EMAIL PROTECTED] Date: 2008/07/18 Fri PM 07:49:19 EDT To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] PL Problem Isn’t1K a little hot for PL tone? David -Original Message- From:Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of tgundo2003 Sent: Friday, July 18, 2008 7:56AM To:Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] PLProblem I need some suggestions. It seems that my users that have newer Motorola Astro series radios have a problem on my Micor UHF repeater where the PL does not always open up their radios. It seems that it's only Astro type radios that have the problem. I have the PL Deveation set at 1K. It's generated internally on the uni-chassis TX PL board. I have 2 GP-300's, 1 MAxtrac, 1GM300, a Yeasu dual band Mobile and a Radio Shack HTX-404 (With an MDC board installed it in! I actually love that little radio) and None of them have any problems decoding the PL. So what's up with the new stuff? It it really picky? what else should I check? Thanks!! Tom W9SRV P.S.- I told them all to buy old radios and be done with it. Besides the TX audio out of the new stuff sucks anyways, IMHO, unless you like listening to over-processed crap ;) Ron Wright, N9EE 727-376-6575 MICRO COMPUTER CONCEPTS Owner 146.64 repeater Tampa Bay, FL No tone, all are welcome. Yahoo! Groups Links
Re: [Repeater-Builder] Re: Programing issues, my SCOM 7K's DTMF tones
The rather painfully obvious question is: did you write down what you were changing? If so, you can go through the changes made and see what needs to be done to reverse the damage, or at least where you made the error. If not then. - Original Message - From: [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com ; [EMAIL PROTECTED] Sent: Tuesday, June 17, 2008 8:15 AM Subject: [Repeater-Builder] Re: Programing issues, my SCOM 7K's DTMF tones Hi Skip and all the guys! The 7K is working just fine. It seems that I have locked out all responses, all the id's are off, no time announcements, no normal announcements (I was programming it to do just that, minimum responses!) The weird thing right now is the controller hears the DTMF, mutes when it decodes the DTMF, but is not executing the commands. If I send a macro to tell me the time or turn the system on or off, (on the phone line or over the air) the 7K mutes the tones, but doesn't execute the command. I did not change any of the priorities of the receivers, just shortened up everything so that when this weekend's special event happens, the 7K system is a linked/slave to Tom's 7330. We are linking 3 or 4 systems together for a special event. I just do not want to hit the MAGIC BUTTON . COLD RESET!!! Anyway, it looks like I fat-fingered something, and a reset is called for, I just don't really look forward to it. My 7K is more than a decade old, was a version 1.14 now its a 2.03b. It is rock solid. It is the heart of my system, controls 2 repeaters (the other system is also now in this same condition too!) I love it! Thanks Bob the gang at SCOM for this great product! 73, Brian, WD9HSY -- Gas prices getting you down? Search AOL Autos for fuel-efficient used cars.
Re: [Repeater-Builder] mice at repeater sights
Consider yourself lucky that the evidence is only on the outside of the cabinet. I have seen much worse on the inside of cabinets. Also consider a mask and gloves when handling the equipment for cleaning and while in the building. Haute(sp?) virus is spread by mice. - Original Message - From: Jed Barton To: Repeater-Builder@yahoogroups.com Sent: Friday, May 23, 2008 11:04 AM Subject: Re: [Repeater-Builder] mice at repeater sights yeah, this was a nice Icom repeater, and let's just say they left evidence of them being there, by releiving themselves on top of it. Now the repeater was still working, but i was horrified at what i saw On May 23, 2008, at 10:56 AM, Eric M. Used to have mice problems with computer systems that were in harsh environments like warehouses and even one in a brick plant. We would spray WD-40 on the inside of the panels of the systems about every six months when we did the PM's on the systems, no more mice. Not sure what was in the spray but the mice didn't like it. Eri c VA3EAM Jed Barton wrote: Some of you pros have delt with this i am sure. A commercial repeater that i do some work on, i went up to the sight after over a year, and let's just say it was a horrible sight. The mice brought the repeater to its knees. Anyone have some advice on getting rid of the little bastards and keeping them away? Anyone else delt with this problem? Mice are evil Thanks, Jed
Re: [Repeater-Builder] Cooling fan
Speaking of issues with fans, I recently had a GR-300 repeater that started emitting a howling sound when users transmitted. Thought it might be a temperature change issue until I got to the site and heard the same noise as soon as I opened the door. Turned out to be the fan in the rear housing somehow causing a microphonic condition in the transmit radio; I suspect a loose shield. The quick fix was to remove the fan from the radio housing and place it directly behind the housing. No more noise, still supplying air to cool the heat sink. Sometimes the little stuff can be very frustrating. Milt N3LTQ
Re: [Repeater-Builder] Mot Micor T74RT3000AA
The unit is a 100 watt UHF transceiver. They can be moved to the 440-450 band if you are willing to do a lot of work and have the proper test equipment (or access to same). Going from memory... The Micor UHF mobiles used a single channel element for frequency determination. The channel element sets the RX frequency injection 21.4 MHz below the operating frequency. The same signal is sent to the transmitter board where it is mixed with another signal from the offset oscillator. If the offset oscillator is 21.4 MHz the radio will then transmit on the same frequency it receives on, ie simplex. If the offset oscillator is 26.4 MHz the transmitter will generate a signal 5 MHz above the receive frequency for use on a repeater. Obviously any drift in the receive element will be reflected in thye transmit signal. The output of the transmit mixer went through a narrow filter that tuned to the transmit frequency range. The filter output fed a low level amplifier, which then fed the PA. This radio can function nicely as a mobile or base station within a limited range of frequencies. As I recall, the receiver was narrow, maybe 1-2 MHz and the transmitter was 500 KHz. Some radios had two offset oscillators and two filters for repeater and simplex operation. Remember that this is 30 year old technology. I'd make sure that the radio works where it is currently built before trying to do any changes in frequency. Changing frequency requires recrystalling the channel element. This is best done by a crystal house such as Bomar or ICM, by sending the element in and requesting that it be recrystalled and temperature compensated. Milt N3LTQ - Original Message - From: pooterwizz [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Friday, April 04, 2008 7:13 AM Subject: [Repeater-Builder] Mot Micor T74RT3000AA Hello fine RF People, I already know this is UHF mobile unit. I have the connector and cable (s). What I need to know since I am new to all this RF stuff and think this would make a good project is, is this all here? Unit was found in an old shed. Lots of corrosion in the PA section. connectors undone and bottom cover plate missing. Not a problem. I want to use this in the 440-450 Mhz HAM band. The only element in it (I understand there should only be one) is for R-451.875MC/1.8340.625KC Mot P/N KXN1024A. Questions, is all of this critter here? Can I add more elements (channels)? Do all these use the same key? (On the Handle) Maybe I can find the key in this estste mess. (I have already found the (Handles) for several pieces of test equipment, etc. There are several keyrings, maybe something will fit this critter! Last, outside of getting the schematics and service manuals which I have not fuly checked for yet but will before I begin messing with this critter, what is needed to make this work in the 440-450 HAM band preferably 5Mhz split for repeater access/use. Thanks in advance, Bruce (PooterWizz) Bagwell KE5TPN (Please note the new Call Sign since my last post If you can hit IRLP node #4640 call me. (Hey, being new, it sure is nice to hear my call sign FIRST! I usually have a scanner going by the PM. Call a few times to let me maybe get my radio up please. Maybe you could email me to set up a contact time at bbagwell AT swbell DOT net. Thanks again! Yahoo! Groups Links
Re: [Repeater-Builder] Linking a Kenwood TKR-750 to an ICOM IC-F521
IIRC, EPTT (Kenwood) is an input not an output. Are you trying to have the Icom key up when the Kenwood receives a signal, or are you trying to have both radios transmit at the same time? Milt N3LTQ - Original Message - From: askjam [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Wednesday, April 02, 2008 12:07 PM Subject: [Repeater-Builder] Linking a Kenwood TKR-750 to an ICOM IC-F521 I'm trying to use an ICOM F521 as a link repeater and interfacing it to an existing Kenwood TKR-750 site repeater and cannot seem to get the pinout below work. It would appear that the EPTT on the ICOM or Kenwood is not triggering. Kenwood TKR-750 Icom F521 Pin 7(DG).Pin 8(Mod. GND) Pin 9(TA).Pin 2(AF OUT) Pin 11(RA)Pin 4(Mod. IN) Pin 16(EPTT)..Pin 5(PTT) Can anyone offer some help? John. Yahoo! Groups Links
Re: [Repeater-Builder] Re: Compa Station Help
Actually, I wouldn't be too concerned about the condition of the rest of the station. You might not be, and I would not be concerned if I had the station or was considering it. I do not know what the original poster's level of experience is, thus my comment. If I was looking at this station I would see a good supply of spare parts, and/or a possible conversion to 220 since it reportedly has a high range transmitter. I would not consider this station a good candidate for a first time project. With no channel elements and a high split radio it will be hard to determine if the station has any problems BEFORE an attempt is made to change frequency. Simply grabbing a set of elements and restuffing them is a sure way to add to your overall level of frustration/stress. If I were going to try to do anything with this unit I would want to find a set of channel elements in the high range. I would then attempt to get the station working in the range that it was built for. Find and if possible fix any issues that are present. Determine what is needed to convert to the lower range. THEN AND ONLY THEN would I attempt to change the frequency of the radio. No, changing the frequency range in which the radio operates is not rocket science, it simply takes a service manual, proper test equipment, time, parts, patience, an understanding of what is going on, and a willingness to learn. Now back to repeater-building. MIlt N3LTQ
Re: [Repeater-Builder] Compa Station Help
Intermittent duty base station that has been robbed of parts. No channel elements in the receiver, probably none in the transmitter. No station control card. No high current leads to the final. As noted by earlier posts this is not a unit that will handle long periods of transmission. Also no antenna relay (not that you need one for what you want to do). Given the number of missing parts I would be very suspicious of the overall condition of the unit. Milt N3LTQ - Original Message - From: [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Friday, March 28, 2008 9:01 PM Subject: Re: [Repeater-Builder] Compa Station Help How about some pictures? They are a little big and some are redundant but hopefully it should give you guys some idea of what I have. http://www.highwayusa.com/motorola/pict0001.jpg http://www.highwayusa.com/motorola/pict0002.jpg http://www.highwayusa.com/motorola/pict0003.jpg http://www.highwayusa.com/motorola/pict0004.jpg http://www.highwayusa.com/motorola/pict0005.jpg Vern On Fri, 28 Mar 2008 19:12:06 -0500 (CDT) Ron Wright [EMAIL PROTECTED] wrote: Vern, Usually the easiest way to find what band and band segment it are on is to look at the Channel Elements, the small cans in the exciter and receiver. They unplug. A label on the top of the cans gives its frequency. However, to prevent them being put back on the same freq some pull the elements. Most always one can get to them thru a panel behind the receiver. Same with some exciters. There were 3 ranges for VHF as someone stated. Wonder what the heat sink looks like. The continuous duty has large 17w x 7h x 6 deep heat sink. Otherwise it is built into the main chassis or is tube amp. Mot made a number of variations of these. They do make good repeaters. Just takes some work. One clue if it is a repeater and not a base station is the card cage usually has a Squelch Gate card. This controls rx to tx keying. I think others gave you lots of good info with the repeater builders site. The power supply tells lots. Might describe it. 73, ron, n9ee/r From: [EMAIL PROTECTED] Date: 2008/03/28 Fri PM 01:19:10 CDT To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Compa Station Help I have a Compa Station with the model number C73RTB-1106C. I am looking for some help figuring out what this is split, etc and how to make it into a repeater. First things first is that there is no power leads hooked up except for the one to the control board box. I can see where there are places for heavy cables from the power supply to the transmitter. Is there seperate power for the receiver or does that come from the ribbon cable? How can I get this thing to key up to see what the TX frequency is? If I find out the TX freq can I sweep the recv side with a freq generator to figure out where it opens up? Are these crystal controlled or can they be adjusted to get the right frequency pair? Thanks, Vern Ron Wright, N9EE 727-376-6575 MICRO COMPUTER CONCEPTS Owner 146.64 repeater Tampa Bay, FL No tone, all are welcome. Yahoo! Groups Links
Re: [Repeater-Builder] Using Alinco DR-605 Dual Band Mobiles for Repeater
The first problem you have is that you are using non type accepted equipment in GMRS. Come to a full stop and seek out some type accested equipment to construct your repeater with. Milt N3LTQ - Original Message - From: briguy1q2w [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Sunday, March 23, 2008 4:14 PM Subject: [Repeater-Builder] Using Alinco DR-605 Dual Band Mobiles for Repeater I am wondering if anyone has experience with setting up two of these radios to work as a GMRS Repeater? We are experimenting with the idea of setting one up in our small town. Will I need a simple controller or interface of some type that may be readily available? Any help in the correct direction would be appreciated! Thanks! Brian/WB2JIX Yahoo! Groups Links
Re: [Repeater-Builder] ICOM FR-3000 / FR-4000 repeater
John, General setup, I'm not directly familure with this unit. The Icom needs to operate as a full duplex base radio instead of as a repeater. The internal controller will most likely not be used, unless it can provide an ID function. This might be done via programming or a switch (Rpt/Local). Bring the audio and COS from the Icom receiver to the Doug Hall voter. Take the audio output of the voter and PTT and feed to the Icom transmitter. Good Luck Milton Engle N3LTQ MD Technical Services, LLC - Original Message - From: John 99-1nwecs.org2@ To: Repeater-Builder@yahoogroups.com Sent: Tuesday, March 11, 2008 4:27 PM Subject: [Repeater-Builder] ICOM FR-3000 / FR-4000 repeater I have an Icom FR-3000 repeater in use. I would like to add a Doug Hall signal to noise voter. I am not sure how to interface the voter into the repeater. I have COR and audio coming from my other receivers into the voter. My question is how to break out the receiver from the repeater, send it out to the voter, and send the voted signal back into the repeater activating the repeater controller transmitter? Can this be done using the internal repeater controller of the Icom? Should I use an external controller? I have the Icom instruction manual. It gives some pin-out information but doesn't seem to have what I am looking for. Is there a detailed service manual for these? Does someone have a copy they can send me? I tried contacting Icom but the systems people were not available to offer any assistance. Thanks in advance, John Liguori Sparta Twp NJ Yahoo! Groups Links
Re: [Repeater-Builder] Re: Low-band MaraTrac Squelch Pots
Bob, The info you need is contained in FMR-1735A-1 dated June 1996 The Audio squelch board in the radio is replaced with HLN5342ESP01 From Pin 9 on the front connector (the former busy light line) on the interconnect board, the signal feeds through JU1510 to pin 12 of J21 the audio board connector. JU1509 and 1511 are open, JU1512 is in. J21 pin 12 is the pin 2 input of U1103. JU1202 is out. IIRC busy light is not used on A7 heads with the remote squelch control option. It's possible that you have a missmatch between the head and audio squelch board. Milt N3LTQ - Original Message - From: Bob M. [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Monday, February 04, 2008 6:26 AM Subject: Re: [Repeater-Builder] Re: Low-band MaraTrac Squelch Pots Thanks to the people who posted the link. I had seen that page earlier but didn't follow the signal off the board. The pot in the control head seems to have its arm and one end connected to ground. The other end goes through some resistors before leaving the control head. I can see the effect of turning the pot down at pin 9 of the control cable; it varies from about 3-5 kOhms. I thought it was just a DC signal or just a varying resistance to ground. The schematic posted doesn't show the wiring from the audio board out to the pot on the control head. I'm guessing that the signal coming into the squelch pot on the audio board is detected audio, since it then feeds the internal squelch pot which sets the gain and threshold of the squelch circuit. I'll have to rethink and evaluate this new information. Bob M. == --- sgreact47 [EMAIL PROTECTED] wrote: Bob, Look here for the modified audio board. http://www.batlabs.com/images/marsqsch.jpg The squelch control circuit is there, uses the Micor, MSF, high speed squelch. Bob M. [EMAIL PROTECTED] wrote: I'm working on a 42-50 MHz MaraTrac with the A7 advanced head that has a squelch pot on it. The squelch is open all the time, and neither the control head pot or the pot inside the radio will close the squelch. Never miss a thing. Make Yahoo your home page. http://www.yahoo.com/r/hs Yahoo! Groups Links
Re: [Repeater-Builder] Re: Micor Repeater - ID?
A community repeater is shared by multiple users, each using a different PL/DPL code. If all users have decoding set up and the mic hung up, no one hears anyone else until the user goes off hook. The hardest part of operating a community repeater system is to educate all users that if someone else is talking they can't barge in and overpower the other user. LTR is so much nicer... Milt N3LTQ - Original Message - From: Mike Benonis [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Monday, February 04, 2008 8:22 AM Subject: Re: [Repeater-Builder] Re: Micor Repeater - ID? What exactly is a community repeater? I've seen references to it, but I haven't seen a definition yet. Best regards, Mike Benonis Electrical Engineering '09 Department of Drama Sound Engineer The University of Virginia [EMAIL PROTECTED] mailto:mjb8h%40virginia.edu KI4RIX On Feb 4, 2008, at 3:55 , sgreact47 wrote: Acually it IS a C64RCB-3105AY which is a eight user comunity repeater. Eric Lemmon [EMAIL PROTECTED] wrote: Mike, The C64RCB-3105AT (I'm pretty sure the Y is actually a T) station is described as: C = Compa Station 64 = 75 watt output in the UHF band RCB = Continuous Duty PA 3 = PL Tone-Coded Squelch 1 = N/A 0 = 1 TX and 1 RX 5 = DC Remote Control AT = Repeater Station You can get more information by looking at the numbers stamped on the various boards. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Mike Benonis Sent: Saturday, February 02, 2008 1:38 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Micor Repeater - ID? Good day, I just picked up what I believe is a Micor repeater at a Hamfest today for free. I'm told the repeater works, but I can't verify that. Here's what I know about it: Form Factor: Rack-Mounted Model Number: C64RCB-3105AY FCC Xmit Info: CC4224C FCC Rcvr Info: RC0080 Frequency: 464.050 MHz (I assume this is TX, but it doesn't say specifically on the label) Cards installed: 2x Four User Control Modules 1x Master Decoder 1x Squelch Gate 1x Station COntrol Module 1x Time Out Timer It has a Motorola power supply in the rack at the bottom. I didn't see any cans mounted in the rack, but I only found one N connector on the back (ublabeled, of course, but it looks like it comes out of a large silver box at the top of the rack with a heatsink on it. I can provide photos of the unit if needed. I'd like to convert this down to the 440 MHz amateur band if possible, for less than say, $1000 in new parts/repairs. Can anyone tell me, based on the information given, if this seems like a reasonable thing to do? If this is a boat anchor, I'm perfectly happy to get rid of it - but I figured, for free, what do I lose? Best regards, Mike Benonis Electrical Engineering '09 Department of Drama Sound Engineer The University of Virginia [EMAIL PROTECTED] mailto:mjb8h%40virginia.edu KI4RIX Yahoo! Groups Links
Re: [Repeater-Builder] 10 Meter Repeater
To be perfectly legal, a controller need to be placed into both units. Being *perfectly* legal costs money and hams are cheap, therefore, usually, only half of the system is legal. Kevin I know of a 6 meter split site repeater in the capitol city of PA that has absolutely NO ID. Most likely a pair of FT-8900's set up as back to back crossband repeaters. Sad Milt N3LTQ
Re: [Repeater-Builder] Re: Gmrs Repeater
The GMRS full power channels are 462.550, 462.575, 462.600, 462.625, 462.650, 462.675, 462.700, 462.725. Deviation is +\- 5KHz. Power output 50 watts + antenna gain, if any. The interstitle channels like 462.5625 are used by the FRS kiddie-talkies. 500mW power, +\- 2.5KHz deviation, no external antennas. Whoever thought that arrangement up had no comprehension of how a radio works. If I were going to try to use GMRS today with the prolifiration of kiddie-talkies out there I would limit my receive radio bandwidth to the 12.5K setting to cut down on the adjacent channel junk, but that means that any radio normally set for GMRS at 25KHz bandwidth will sound crappy. Thank the FCC and the radio manufacturers for killing off a good service. Milt N3LTQ - Original Message - From: [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Friday, January 25, 2008 10:16 AM Subject: Re: [Repeater-Builder] Re: Gmrs Repeater I was describing the many bandwidth options offered in many new PC programmable commercial two-way radios today. Maybe we're looking at two different things but I see GMRS channels as 12.5Khz apart from each other. Channel one for example is 462.5500 where channel two is 462.5625. Gary wd8chl [EMAIL PROTECTED] wrote: [EMAIL PROTECTED] wrote: Paul, the underlying and unexpected contridiction here was not between 15Khz vs. 20Khz channel spacing but instead between 20Khz and 25Khz channels more commonly found on UHF which as you know is where GMRS resides. Historically there's more than enough guard between channels to compensate for slight overdeviation or slight drift off channel but now everybody wants to tighten things up so new gear is coming stock with 4Khz max dev associated with 20Khz channels vs. 5Khz dev which we've all enjoyed for years on 25/30Khz channels. Seems a bit odd of them to expect no interference problems from +/-5Khz peak dev on a 20Khz max channel but it is better for us users to have the option I suppose. Gary Huh? GMRS channels are still spaced 25 KHz apart. If someone is making radios with 20KHz spacing, they are illegal-in the US... Yahoo! Groups Links Yahoo! Groups Links
Re: [Repeater-Builder] VHF Repeater Antenna Choice
The PD220 has 5.25dB gain and 18 degrees vertical beamwidth. The DB222 has 3dB gain in the omni configuration, and 36 degrees vertical beamwidth. Vertical beamwidth is measured at the 3dB points on main lobe of the horizontal axis plot, so divide the published number in half and you can easily plot the main lobe pattern on graph paper using the installed height on the tower, and see what might or might not be an issue. | INSTALLED HEIGHT |\ | \ANGLE |\ | \ |\ _|_\___ GROUND The above is a very simplified idea of what you will be plotting. The vertical component is the tower, pick a convienient scale for height. The horizantal component is the ground elevation, be sure to keep the scale the same and add in any hills, valleys etc. as shown on a topo map. ANGLE is 1/2 of the published vertical beamwidth. INSTALLED HEIGHT is an imaginary horizontal line at the base of the antenna (or the center, or the top, it's just a reference line and the ANGLE is measured from it toward GROUND). The point where the line representing ANGLE meets the line representing GROUND is the approximate point where the -3dB point of the main lobe of the antenna will meet the ground. Other minor lobes, reflections etc. will give more close in fill coverage, but for planning and comparison purposes this will give you a good idea of what you might expect. Using the above antenna numbers, the PD220 main lobe will be 9 degrees below the imaginary horizontal line at the antenna base, and the DB-222 will be 18 degrees below the imaginary horizontal line at the antenna base. Therefore, the main lobe of the PD220 will touch down further away from the tower than the main lobe of the DB-222. Depending on the geography this may or may not make a difference in the coverage, it's just one of the many factors to consider. In general, the lower the gain of the antenna, the greater the vertical beamwidth. Just for fun try plotting a quarterwave antenna. The DB-201 ground plane (0dB gain) is speced at 78 degrees vertical beamwidth, thus the main lobe is 39 degrees below the imaginary horizontal line at the antenna base. ;-) BTW using a topo map and plotting radials around the repeater site can be a good way to get to know what things look like from your site. Of course buildings are not shown, but finding the hills and valleys can give you a new perspective on why things do or don't work. Once I had to try and figure out why an 800 MHz control station was not properly getting into a distant repeater. After getting the topo out and locating the repeater and control station and adding in the tower height at both ends of the path, I found that the direct, straight line path was through two hilltops. The station was getting by (poorly) on the indirect reflected path(s) that existed. The only way to solve the problem would have been to relocate the base to the top of the nearest hill. Good luck Milt N3LTQ - Original Message - From: Tony L. [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Tuesday, November 27, 2007 11:47 AM Subject: [Repeater-Builder] VHF Repeater Antenna Choice Any comments on the difference between expected antenna patterns and coverage on a DB222 vs. Celwave/RFS PD220? I'm using a PD220 and find the local coverage to be somewhat spotty, but coverage 20 miles away to be excellent. Is this typical of the PD220? Would a DB222 fill local areas any better? --- In Repeater-Builder@yahoogroups.com, skipp025 [EMAIL PROTECTED] wrote: Dipole phasing is not easy even for the Decibel 420 type antennas. It is common for very sharp nearfield nulls and cancel areas expecially near and underneath a mountain top mounted antenna. I label the effect something similar to what I call unwanted nearfield/local re-entrant energy. Less of a similar antenna in the case of the DB-408 would have less gain but less close-in and below problematic areas. It would also have a different vertical radiation angle. Using at least one of all the Decibel DB-408 and DB-420 type antennas from a mountain top repeater site... I can tell you first hand there is quite a bit of difference in portable and distant in-building coverage using the higher gain Decibel DB-420 antenna. There is also something to be said for what I call the antenna capture area, which is the shear amount of dipole surface area (metal) spaced up and down many wave-lengths on the tower. In most cases there should never be too much antenna but there can be the wrong antenna for an application and location. One sidebar I noticed in your post... you weren't using a Decibel DB-420 Brand Antenna. The Signals Brand Antenna first used in your system is a different animal indeed. cheers, s. Chuck Kelsey kelsey@ wrote: We had a DB-420 style antenna (actually it was made by Signals, but it was folded-dipole design) on our UHF
Re: [Repeater-Builder] Site noise
Duplexers are Telwave BpBr 4 cavity. added 2 more BpBr cavities at 104.9. To my surprise I was getting -8 dbm You can try a stub to NOTCH 104.9, but I would suggest using 1-2 BANDPASS cavities tuned to your receive frequency. BPBR cans are pretty wide open once you get past the operating range. Milt N3LTQ
Re: [Repeater-Builder] Micor UHF PA
Jim, You might be thinking about the 33pf(? value) on the collector/emitter junction on the flat pack RF transistors. Or the leaching problem that is mentioned in the service manual. I always replaced the chip caps on the base/emitter and collector/emitter junctions when we had to replace a defective transistor. There were PK-xxx packages for replacing the lower level transistors that included the transistor, chip caps and solder. Milt N3LTQ - Original Message - From: Jim Russell To: Repeater-Builder@yahoogroups.com Sent: Friday, September 28, 2007 11:24 PM Subject: [Repeater-Builder] Micor UHF PA Ok guys help this old man out. I worked in a Motorola Shop back in the 80's. I seem to remember a problem with Micor UHF PA's where the solder connection on a perticular chip capacitor would go bad causing the power to drop to next to nothing. I think the solution was to resolder the cap with silver solder. Do any of you know of a better solution. I have one of the animals acting intermittant. Jim WK5Y
